Reprogramming Mega Man 4's Charged Shot - Behind the Code

Cut the charge time in half? How about a damage boost? Focus on the process of reverse engineering code in this episode. Lots of code-hopping!
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Music by:
/ hariboosx
/ @wolfandraven
Featured Game Genie Codes:
(Take note that I have not tested all of these with a real cartridge)
Half Speed Charged Shot: GVEEGAZZ, ESEEIAAZ, LEEETEVL
Half Speed Broken sound: ZUOALAGT, POEEAAZU
Half speed, sound fixed, mid-level shot: ZUOALAGT, POEEAAZU, ZXOAYEGS
Start Buster at 1/2 Charge: ZUVEVGAA
Super Charged Shot (Extra Damage): OXNETZSX
Default to (Fully) Charged Shot: AXKESKAP, IUSAOGPX
Charged-Up Sound Fun (Use to replace charged up looping sound) -
Boss Door: GXOELAYX
Explosion: IXOELAYZ
"You Got" Music: GOOELAYZ
#MEGAMAN #HACKING #BEHINDTHECODE

[@FeralInferno]

It'd be kinda cool to see the code of the Magnet Missile from Mega Man 3 played around with. Those physics always intrigued me.

[@TroyBlackford]

Ooh, I second this! Great idea!

[@shimon4531]

@@TroyBlackford I third this.

[@VictorMR01]

I know how it works: When the projectile is created, it will go in the direction where the player is, when the X position of the projectile and that of Megaman are the same, the projectile checks whether the Player is above him or below.

[@tomyyoung2624]

Yes TPM Yes UIFI

[@KnakuanaRka]

I would love to see the physics behind the Gemini Laser.

[@ScrambledAndBenedict]

I got one for you man. Can you make a code to slow down the speeder bike segment of Battletoads? I don't even know if it's possible, but that'd be real cool.

[@DisplacedGamers]

Whoa. That sounds super useful!

[@OM19_MO79]

@@DisplacedGamers It makes me wonder how further would it break an already broken stage (should I say "game"?).

[@ejmc6378]

Now THAT'S a good a idea!

[@Favourites669]

Excellent idea. It'd be so cool to finally be able to see what lies beyond that goddamned stage I could never beat.

[@barbedwire83]

And this is when I realize I was actually rather good at Battletoads when I was a kid. I was able to make it to the sewer stage easily without using continues. Damn those fan blades, though!

[@elecboy5126]

Fire man’s code can be described with two sentences. Run back and forth across the room. If mega man shoots or gets close, shoot. It’s hilarious, considering how tough he seems if you fight him as spammy as you fight everyone else

[@jennjennjenn61992]

its a tad more than that

[@QuartzQuadrantRadio]

Run back and fourth, shoot when blue boy shoots or gets close.

[@Sephiel263]

I would love to know how Quick Man's AI works. It seems like it is actually random if he'll run, jump, or jump and shoot but naturally that can't be. There has to be some logic behind it.

[@dracmeister]

Quick Man's AI is bugged... at least in the initial boss arena before the boss rush. Quick Man's boss arena in his stage isn't exactly designed for him; he gets stuck a lot messing up his AI. Though unfortunately there is some literal fuzziness to his AI just like Shadow Man.

[@jironamos7650]

@@dracmeister compared to Shadow Man, Quick Man is seriously bugged, older prototypes of MM2 had a plain square box for its boss room, since its only weakness would have been Time Stopper (that could drain all its life), however, since the fight was too easy that way, they decided to add more stuff to the stage so you could use the obstacles to plant Crash Bombs, its second weakness.

[@dracmeister]

@@jironamos7650 thing is at least Shadow Man works eventhough THAT slide can be BS at times. Quick Man, after some digging, actually moves a bit too many pixels forward everytime he moves and since there isn't any algo in him that makes him stop in the correct amount of pixels if his speed in pixels is less pixels than he is towards a wall, he walks into it and only then the game stops him from clipping into the floor.

[@BewbsOP]

7:47 This is such a good reaction

[@TroyBlackford]

This is one of the best ones yet! I definitely loved this one! Maybe it would be cool to see how level design in these old NES titles works in terms of the programming: how boundaries like walls and ceilings work in the code, how ladders and doors are implemented. And how just the grid of backgrounds are 'imbued' with these properties, as well: is it on a tile by tile basis, or are the backgrounds simply stacked up in code and then separate code gives them their properties like "characters can't go through this pixel, they can climb up this pixel." Lots of great platformers this would work on. Also, some info about Game Boy or SNES titles would be most welcome!

[@tommyzorera]

Mega Man 4 - the game the ruined the series by making you listen to that charging sound for the rest of your life.

[@ScrambledAndBenedict]

Owwwwwwwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwerwer-PSQUEWWW!!!

[@Adamwinters]

Haha, so true. It is the worst part of the progression for this and future games.

[@DisplacedGamers]

If you are into patching ROMs, pick up "MM4 - Charge Shot Sound Fade Out" from MetHy.

[@teranokitty]

The worst thing about it is how it eats sound channels so the music suffers in addition to the charge sound being so loud.

[@ultrairrelevantnobody1862]

Even though 4 is critically a massive improvement over 1-3.

[@vercetii1]

Dr. Light could learn something watching this video 😆

[@RadikAlice]

Man, your videos are always so good. I wish you nothing but the best

[@rogercameron6912]

In general, I loved that the Charged Shot took away the tedium of the weapon weaknesses. The damage levels of charges: I wish it was 1, 2, and then 4 or 5, because it takes so long to charge.

[@Red_Biker_Dude]

What the actual fuck... Excuse me WHAT?

[@phonicshfi]

This series has made me curious about the tools Codemasters used to find and publish their original Game Genie codes. Did they just dump retail games to a dev kit and do the same kind of process you go through in a Behind the Code video?

[@jess648]

I think they created a system that interrupts a game before starting and modifies RAM values on the cartridge

[@nickwallette6201]

We are so spoiled by being able to watch RAM live on a high resolution display. Those poor devs...

[@raafmaat]

I dont think they did really.... i remember almost all of the codes they published were simple things you could easily find by just inspecting RAM and looking what values change by doing something in-game etc! i barely ever came across codes that would have required analysis of the cartridges storage (ROM)

[@LevitatingCups]

Gotta love that you can bother to translate them to game genie codes.

[@ReaverPrime]

Seeing Skull Man's reactive behavior reminded me that Freeze Man from MM7 is essentially the same. He will stand there and just give you the "Come get some" hand wave until you move or shoot.

[@CptJistuce]

The "crash man dance" is a hilarious usage of the concept. You walk away at the start of the battle, he walks towards you, and as he turns around to walk away you turn around and follow him. Lather, rinse, repeat.

[@トト-c9l]

とても参考になりました。ありがとうございます。Thank you. It is helpful for learning debugging.

[@JoeStuffzAlt]

They did some cool things with it in the Mega Man X series. The boss powers get charged, and in X3, had some pretty nice effects

[@jn1211]

the way you describe watching the hex code to figure out what's going on is basically the exact method I used to hack my bluetooth on my volcano vaporizer, though in reverse because i could only throw numbers at addresses. I eventually got full control of the thing at the hex level completely outside the official app[which had broken for me]

[@TheRogueMaverick]

I’d personally like a follow up on the Charge Shot as it functions in Mega Man 6! It has different properties than what’s found in 4.

[@AtomFry]

It would be interesting to see a breakdown of the Big Eye enemy from mega man 1. Urban legend has it that it will do a big jump (so you can run under it) if you jump at the right moment and others say it’s totally random whether it does the big hop or the little hop and has nothing to do with your input.

[@sackboy1665]

Skull man is actually very simple if left/right is pressed: shoot three aimable shots, then start listening for inputs again if B is pressed: jump twice, activate skull barrier, run forward, and then wait a moment before listening for inputs again

[@Red_Biker_Dude]

That's not exactly how he works First of all, his response to pressing B is only jumping once, not twice (then using skull barrier etc.). Something else you forgot to mention is that skull man can't repeat the same action 3 times in a row. So, if you press left/right 3 times, on the third press he'll jump instead of shooting

[@plaguis1391]

Very rarely do I find a channel that immediately goes into "instant favorites" category. This is some truly fascinating stuff

[@no64256]

0:00 the fact that you ordered them "1 2 3 5 4 6" Pains me greatly

[@davidthecommenter]

So going from 00 to 01 summons Rush? Wow, they must have a *strong* bond if Rock's next item unit is literally Robot's Best Friend

[@sryx]

I spent a decent amount of time trying to workout a game genie code that would set the default time for the NWC game to the competition value. In the original NWC there are dip switches for setting the time with the competition time (of about 6.5 minutes) requiring a specific setting. But when you load the NWC rom on a flash cart there aren't dip switches to set so you only get just under 5 minutes. Watching this video gave me a bunch of ideas of how to tackle this :)

[@Sonicgott]

God I love this channel. My inner child and inner nerd are finally getting along.

[@gnpar]

Really loved this one. Getting a peek at your process for reverse engineering this games was very instructive.

[@GustavoValdiviesso]

Suggestion for future episodes: Mega Man 2 was the first one in the series to have a charged shot: Heat Man's weapon. It would be interesting to know how different the code is between the two games, as you did with Ninja Gaiden' jump mechanics.

[@DisplacedGamers]

Hmm. Good point. Thanks, Gustavo. I will make note of that.

[@ccanaves]

Awesome video as usual!. Can you do some videos about RPG damage formulas and how attack/defense works in the code, etc? Captain Tsubasa 2 is a great game with A LOT of stats, criticals, etc.

[@DoomRater]

A fully charged mega buster sounding like a boss door? Yes please!

[@dsuess]

I wish Mesen and Mesen-S were still in full development and not archived. They are great emulators with a rich set of tools!

[@DisplacedGamers]

They have really blown me away. In fact, I feel like they set the bar for debugging capabilities for emulators.

[@michaelclarkj]

Big fan of mega man, no experience with this kind of coding but was still very interested. Well done. There might be some interesting story telling looking through Mike Tyson's Punch Out. It's a beloved game by many, with deep speedgaming lore, and so many curiosities in its playthrough. Not sure what you might find in your code walking.

[@johnmarkther2218]

You make really cool stuff! Been following for a while and you've given me a better appreciation for the more technical side of older games. Crazy how any of these worked haha, a lot of creative nonsense

[@Pulmonox]

In some Mega Man games you're given weapons that allow you to direct their fire in any of the 8 cardinal directions. The most famous of this being the Metal Blade in Mega Man 2, but the Shadow Blade and the Pharaoh Shot in Mega Mans 3 and 4 respectively also have this trait. Is there a way to maniuplate the code to apply this multi-directional ability to other weapons in the game (or even the Mega Buster) allowing Mega Man to shoot in more than one direction? That would be a fascinating prospect, I think.

[@framedude]

Well, seeing as it was possible to see how Skull Man's AI worked, there's 3 Things I'd Like to know: 1: How does Guts Man decide if it wants to jump left or right? 2: How do Mets (Mettaurs) know if you walk in front of them? 3: How do the Hitboxes of Metal Man's Crushers work?

[@Red_Biker_Dude]

For question 1: rng, nothing else Fir question 3: if they are going down, the chain has a hitbox, if they are going up, the chain doesn't have a hitbox

[@heitortremor]

Very good explanations. The editing really clarifies a lot of the intricate aspects!

[@DisplacedGamers]

Thank you!

[@Kj16V]

5:57 Skullman: Aha! Prepare to meet your doom, Megafool! Megaman: ¬_¬ Skullman: Well? Let's have at you then! Megaman: -_- Skullman: What is this? What are we doing? Megaman: ¬_¬ Skullman: Um, I'm not programmed for this. Sooo you wanna just talk, or play video games or something? I dunno...

[@wtcvidman]

Good video, but I wish people would stop calling the basic Arm Cannon the Mega Buster. The Mega Buster *is* the plasma charge shot. The term Mega Buster did not exist until Mega Man 4 and it was used to describe the charge shot that was added to the Arm Cannon. As someone who grew up with the very first game and was reading a lot of video game literature at the time, the term Mega Buster never appeared until the release of MM4. It was described as the new Mega Buster. The Arm Cannon was not new, but the variable plasma charge it was given starting with MM4 was new.

[@BagOfMagicFood]

No, the game calls it the New Mega Buster, therefore an upgrade to the prior Mega Buster. Just because they forgot to localize the name of the Rock Buster in earlier games doesn't mean the name didn't exist! (Or did it?)

[@wtcvidman]

@BagOfMagicFood The name Mega Buster or Rock Buster simply didn't exist until MM4/RM4. The "new" part was not even consistently used & was not capitalized on the back of MM4's box to discern from a possible plain old Mega Buster, so it was just a descriptor. The manual describes it as the miraculous Mega Buster, which it none of the previous MM manuals described the Arm Cannon itself. It also talks about summoning the full power of the Mega Buster (since the charge can be powered up to variable levels) and uses the same words ("summon the full power") when describing the Pharaoh Shot, which again is just a chargeable ammo/weapon you can get & use through the Arm Cannon & can be shot at variable charged power levels. In both cases, that "summon the full power" phrase is used to describe the charged ammo being shot and not the Arm Cannon itself. The way I see it, the only thing new about the Arm Cannon starting with MM4 was the charge shot, so either way, if new is used or not, the term Mega Buster refers to the actual charge shot itself. Maybe Capcom is trying to rewrite history now by retconning it, but back in the day, it was clear that the charge shot itself was the Mega Buster. Even the name Mega Buster is suggestive that it's beyond the normal Arm Cannon plasma shot, as in it's used to take out bigger and tougher enemies. What I mean by this is that the purpose of the term Mega Buster is to distinguish between regular Arm Cannon firepower seen in MM1-3 & in MM4 & beyond when not holding B and the charged firepower when holding B. So Mega Buster was used to distinguish the unremarkable regular shots of the Arm Cannon in all previous games & in MM4 when shooting regularly from the impressive/miraculous or "Mega" charged shots seen starting in MM4.

[@BagOfMagicFood]

​@@wtcvidman Well, the "Mega" part comes from Mega's name, but maybe it didn't bust as well before?

[@BagOfMagicFood]

Now this has got me curious again: What is it in MegaMan 4's code that _requires_ you to fire a normal shot before charging up, whereas later MegaMan games will count the holding of B since a time that MegaMan couldn't fire at all, such as during a slide or a screen transition? I've also heard that MegaMan 5 doesn't allow the charge level to increase during sliding, even though you hear the sound effect reach its peak in the same amount of time. On the other hand, when you slide through a tunnel while charged up in MegaMan 4, you can let go of the B button to suddenly stop the sound effect and freeze the palette cycle, then re-press the button to resume the sound and palette cycling just as quickly.

[@doomman7349]

I NEED a video explaining Quick Man's AI in Mega Man 2

[@NrgSpoon]

After finding out how the charge works as an incrementing counter, my thought to half the charge time would have been to just find a way to increment twice instead of once. I suppose there's no easy replacement point to get that done cleanly in this case.

[@InsaneFirebat]

Yesterday I was watching this and had to stop to go label/comment stuff in Mesen. Spent at least an hour trying to make the debugger look pretty and now I hate Mesen and love the guy that already disassembled the game even more. Gonna finish watching the video now. Thanks for these videos, and for showing how you work through unknown code.

[@ernestogutierrez7877]

i have new respect for all those homebrew nes games hackers this is certainly a mix of skill, passion and love for the game kudos on the amazing explanation :D

[@jamminjago]

Mega Man 4 is one of my favorites in the series. I like the Mega Buster and the powers a bit more balanced than in the past. To your question if the mega buster reduced the need for using other powers the answer is yes. The developers always appeared to compensate for this ability. More regular enemies that were chunky. And the bosses were no where near as affected by their weakness as they were in the past. In mega man 1-3 you could absolutely destroy bosses if you had their weakness sometimes with only few shots. Not only that but they had secondary weaknesses in 2 and 3. You had the their primary weakness which just obliterated them, and the secondary which was usually strong enough to take them down in about 8 shots. In mega man 4 their primary weakness is even less effective than the secondary weaknesses in previous games and I'm not sure if they even have secondary weaknesses in 4.

[@Red_Biker_Dude]

My opinion on the charge buster: barely useful, just use the normal uncharged buster, it leaves you way less vulnerable when missing a shot. Not to mention the fact that charge buster is banned in the no miss challenge. The only time when I use the charge buster is in bright man's fight Edit: also, seing cut man's ai would be fun

15:56 the $9096 on the left side should read $8096

[@internetuser8922]

0:01 - this is super nit-picky, but the order of the games shown here is 1, 2, 3, 5, 4, 6. Really not a big deal at all, it just stood out to me. These videos you make are super awesome though. I'm a software engineer, but only use high-level languages like C#, so learning about ASM is really interesting to me, especially in this context.

[@AntonyCannon]

Insane prowess! Good video :)

[@DekuLord]

I'd love to see an investigation into the sudden drop when the lifts open in Guts Man's level in the first game. I have a suspicion that the game constantly imparts a downward force on Mega Man, even when standing on the ground and jump moves him upward at a set rate, but I don't have any familiarity with assembly to confirm that is happening.

[@cactoidpinata]

Thanks for another great video! The Behind the Code series is neat, but I really liked your videos on analog video. Would it be possible to do more of those? Or, better yet, if you're knowledgeable about line multiplying analog sources for fixed pixel displays, I'd be super interested in that!

[@DisplacedGamers]

Hey Andrew. Actually... I have a video-related video coming up next if things go according to plan.

[@cactoidpinata]

@@DisplacedGamers Excellent, I look forward to it!

[@ImSquiggs]

I owned Mega Man 2, Mega Man 3 and Mega Man 4 growing up, and I disliked 4 only because of the Charge Shot. I really liked the tight button-mash shooting from 2 and 3 and felt it actually lost something to have this charge shot that blasts through everything. I also didn't like needing to hold it down all the time, especially because in Mega Man 4 the charge sound overwrites one of the music channels and kills one of the best parts of the Mega Man series -- those sick OG Famitracker beats. MM3 will always be my favourite, MM2 close second, and although there are other reasons to dislike 4/5/6 compared to 2/3 the main reason for me will always be the inclusion of the Charge Shot.

[@ShinoSarna]

If you'd be looking for a different game to cover, it would be cool to cover how Elite handles 3D graphics on the NES.

[@IronMan3582]

How about a code or a ROM Hack that brings a feature introduced in Mega Man 8 and brought back in Mega Man 11: the Mega Buster charges on its own whenever you are not firing. I thought that was so incredibly useful, and allowed you to use a turbo controller without having to toggle the switch on and off. Can we get something like that? I can live with the charge time, I just want it to charge on its own

[@6vibe150]

What’s up we got gamings John Stossel eyewitness news here.

[@boltcrank5259]

I dont know if u were aware, but in megaman 3 there is a cheat that if you jump into any deathpit, and if my memory still works, doing so while pressing select (dont remember which button tbh) on controller 2, will cut the music, not kill megaman and he will gain a super jump of sorts and get out of the pit, i discovered this by accident long loooong time ago haha, it would be really cool to see what really happened there, code wise speaking.

[@logananderon9693]

Thanks for the good tutorial.

[@CreamusG]

The only reason I hate the charge shot, and I mean the only reason, is the freaking noise. You basically want to keep it always charged because hey, free big hit, so 90% of the game you just hear the charging sound.

[@tarotcard0371]

If it's okay to request a topic, I'd like to see a code to decrease the movement speed of towns caves etc for the Gameboy version Dragon Quest 3 (Dragon Warrior 3) that doesn't have any visual glitches. As it stands, one such code gets close, but it causes the back 2 party members to jitter a bit as the game repeatedly tries to increase the player's speed every step. I myself got decently close to making a perfected version of this, but hit a wall and haven't been able to make progress since. All I know is that movement speed is tied to CCB0, but the code at CCEE can effect both it and the tileset.

[@hotmultimedia]

cool stuff! how about a video where you reverse engineer how the enemy AI works in some megaman games (3 or 5 are my favourites) and change behavior of something maybe

[@miketate3445]

I can't stand the charge shot for one very real reason: There is a charge noise stealing a music channel for the entire game.

[@DisplacedGamers]

Mega Man games have such great music. Interrupting with the constant charge noise just doesn't make sense!

[@Valientlink]

I hated this feature mostly because you'd hear it over the music. At least in Megaman 5 the charging sound would die off if another sound happened right after the charging began, so you could enjoy those sweet tunes. Then in Megaman 6 they fixed that and it was back to RIP music. Then of course the anniversary releases just played an mp3 or something for the music, and the charge sound happens to be 50x louder.

[@stevenstark-com]

my OCD brain broke when you put the order of title screens as : 123546 ( but in roman numerals )

[@DisplacedGamers]

If only I could change it after the upload, right?

[@stevenstark-com]

@@DisplacedGamers heh yeah, it's no big deal or anything. just something that stood out to me

[@GrayBlood1331]

Ok so I played around with Mesen a bit and was able to kind of (but not really, sorta) figure out how the timer (where it counts down in the level) in SMB3. And it made we wish that mesen could do certain things. For example, let's say I want to figure out where the memory for the number of coins you have is located. And let's say you currently have 4. It would be nice to filter out any memory values that aren't "04". go back to the game, unpause, collect another coin, pause, filter filter out any memory that didn't change to 5, ect... basically a generic game trainer. Same deal with branching statements. Play the game without doing a certain thing e.g. breaking a block, filter out any branching conditionals that were considered and taken, unpause, break a block, filter out any branching conditionals that were considered and not taken and so on to isolate which bit of code is related to the action you are doing. It seems like that would make it a lot easier to figure out what's going on.

[@GreatFox42]

Yeah I'm a huge fan of Megaman, and 4 is actually my favorite funnily enough. I wonder how many bytes need changing to alter any of the games' weakness cycle. I doubt you could fit a total recycling on a genie code, but maybe you could make each boss weak to everything, or all weak to the same weapon, or something. Or go wild and skip the genie requirement and just play with the cycles to see what sort of mayhem you can cause.

[@vuurniacsquarewave5091]

A lot, because every enemy in the game has a full list of damage values they receive from each weapon. So with 3 bytes you could change three entries in that humongous list.

[@andrew_stamps]

I always hated that the middle shot didn't do extra damage, and if it doesn't have a bigger hit box then it's useless. Can the middle shot be given a damage value of 2?

[@vuurniacsquarewave5091]

It allows you to deliver rapid fire easier, because your first shot will be fired by releasing the B button, and then at the next press you will immediately fire again.

[@andrew_stamps]

@@vuurniacsquarewave5091 I don't think so. Mainly because the middle shot doesn't do extra damage or have a bigger hit box, it would be faster to just spam regular shots, or use the normal shot for incomplete charges, and not give you a shot that seems more powerful but isnt.

[@BBHood217]

Can I reprogram the health filling sound so that it doesn't completely mute the music while it's playing?

[@DisplacedGamers]

Shouldn't be too difficult, I imagine.

[@orlandoturbo6431]

How do they get NES games to run on the Turbografx 16.I seen a video of Mega Man running on Turbografx16.

[@drewp.weiner5065]

Charge shot debuted in Mega Man 2 :)

[@Red_Biker_Dude]

No it didn't? I guess you are talking about atomic fire?

[@Vistico93]

I hated that the "large pellet" was no different than your standard shot. At least in Mega Man X, the half-way there charged shot had some properties your "lemons" did not. For something you have to use a lot in Mega Man IV, the noise of the chargeup was annoying. It would've been nice if it could've been turned off or simply conveyed graphically I also tended to avoid using robot master weapons within a stage because of how annoying it is on NES versions of the game to access them. It would've been nice if we could just push select to either cycle through them or to at least cancel the special ability (and go back to buster) instead of having to pause the game again to reselect the buster

[@twistedsoul]

GKOELAYZ // No fully charged sound GKEEGAZZ // No charging sound (MM4 USA) This is achieved by patching the values at 808C and 809B with the value $44. A silent SFX.

[@DisplacedGamers]

Nice!

[@3xperiment8]

Can you do a Dithering on the SNES video?

[@miketava]

Without the game genie constraint can you attempt porting the charged shot code to the other NES Mega Man titles?

[@DisplacedGamers]

If one were to do that, I think you'd want to take the charged shot code from Mega Man 5 (at least) because it is a bit more optimized. The MM4 code is rather messy and feels unoptimized.

[@tejonBiker]

Nice video about reverse engineering, Capcom release 6 games for one console, now we got nothing, so sad :(

[@Omnituens]

Is there a reason they didn't set the damage to 3 rather than doing (2*1)+1? Hold over from an earlier implementation maybe?

[@davidmcgill1000]

Guess they expected to modify default damage somewhere else, like with a powerup. So they multiplied by 3 instead of forcing a value.

[@kstanni87]

Maybe give the game faster text on everything ?

[@mega_hackpro8484]

18:48 oh fu**** super damage........

[@DuelingShade]

Okay so right off the bat when you're showing the title screens of the first six games, 4 and 5 are switched. Right now they are in the order of 1,2,3,5,4,6.

[@babagryva5954]

i love megaman

[@yeolemillinial8295]

Crash man from 2 is pretty predictable because he always jumps when you shot and you can kinda control his movement at the same time. I always fight him first on casual runs for that reason

[@fasgamboa]

More MM!

[@licksorestockpile1190]

dont have any specific game in mind. will watch ANY behind the code

[@matthewsadler6197]

I must say that I absolutely love the NES Mega Man games however I have to say two specific things about this installment. First why in the blue hell does it take so long for the robot master's energy take to charge up and also Dive Man is an absolute prick. Oh and I also forgot why did they ruin the Rush Jet it was fine in the series' 3rd installment!! Anyway there is my two cents. Lol

[@Red_Biker_Dude]

Rush jet was overpowered in mega man 3

[@omegarugal9283]

nice

[@hgbugalou]

Now make a video adding the charge shot to MM2 or 3. 😁

[@Deus69xxx1]

why is your megaman number progression on the screen showing 1-6, 1, 2, 3, 5, 4, 6? xD

[@bredmond812]

I love your "Behind the Code" series. It really inspires me to continue learning 6502 assembly language.

[@TheMikeyb86]

Dooo it! I'd love to see someone recreate Mega Man 9 and 10 as close as possible in 6502.

[@ccricers]

Stretch goal: recreate Shovel Knight in 6502

[@somerobloxdude3699]

mega man 7 in 6502

[@SuperfluousMoniker]

Try breaking down the AI of Bright Man in Mega Man 4. The attack he uses is based on how much health he has remaining. You can exploit this by shooting him once with the default shot before hitting him with the Rain Flush will prevent him from using his Time Stop attack on you.

[@danmanx2]

I think you're really onto something with these Behind the Code videos. They are extremely entertaining. My request is Rampage on NES. Think about it. Punching a building down in one shot, super speed, giant leaps. I'm sure you could do it in 20 minutes! Again, thanks for the great content.

[@drewirons2646]

Is it theoretically possible to eliminate the full charged up sound so we can hold that button all day long and still listen to those beautiful BGMs?

[@lulkLogan]

^^asking the real questions

[@twistedsoul]

You could probably NOP 808d and 809c, that way the JSR to the sound playback routine during the charge is never called.

[@drewirons2646]

@@twistedsoul I wish I understood what that means and could make my own game genie code

[@twistedsoul]

Possible codes // Skip charging sound XVAEIE XVAETE XVAEYE // Skip Fully charged sound XVPEGE XVPEIE XVPETE Unfortunately it's not possible to skip both sounds in less than 3 GG codes. Someone more clever than me can modify the Sound Effects 22 and 27 so that their first byte is $17, that will cause the sound engine to stop the sound effect immediately and that would only need two GG codes. I was unable to locate which bank they live in though, possibly banks 1D, 1E or 1F. But I don't know where those banks are mapped to during the game loop so patching them with a GG code might have some unintended side-effects since the banks are only switched in when a sound effect is needed according to these documents: www.romhacking.net/?page=documents&category=&platform=&game=1074&author=&perpage=20&level=&title=&desc=&docsearch=Go

[@drewirons2646]

@@twistedsoul wow thank you, I will have to try this out later!

[@warmCabin]

How about Crashman? He jumps when you shoot, or after a timer expires if you don't shoot. But if he's the first boss you visit, that timer *never expires.*

[@DisplacedGamers]

Hmm. That sounds familiar. I think I dove into Skull Man first for getting footage. I didn't look at his a.i. in code - only did a bit of commentary on it.

[@Animebryan2]

@@DisplacedGamers That whole thing with Skull Man not moving until you move was something I never noticed, but I have noticed it with Freeze Man from MM7.

[@Magus12000BC]

Gemini Man's first faze doesn't shoot unless you do. Toad Man jumps after being shot or when you get close. Proto (Break) Man doesn't shoot unless he is close to you and facing you. Gamma's second faze doesn't fire if you're on the edge of the screen. Elec Man's shots can be interrupted if you shoot him when his arms are up. Fire Man shoots when you do. Bomb Man jumps over you when you get close in a similar fashion that Metal Man does. I am probably forgetting a few. But the other robot master seem to fall into two categories. Ones that follow a strict pattern like Ring Man. And ones that have an RNG subroutine like Shadow Man. Not too many I can think of that change behavior directly to you other than the ones I listed.

[@feature-creature]

Just watched the new Video Game Animation Study video on Mega Man and was hoping you'd tackle the series soon as well. Turns out I just had to wait 3 days and it was just as good as I'd hoped! Happy about a bit less focus on the code, too-I love the peek behind the curtain but so much of it is lost on me that it could get a bit much.

[@kri249]

Well this just made my morning. It's always a good day when a new Behind the code episode is released. I didn't know Megaman bosses had AI. I'd definitely love to see delved into on a video.

[@spocktacular1701e]

It is not AI. It's just regular logic. You need a feedback mechanism to produce learning in AI. The author of the video is using the term wrong.

[@kri249]

@@spocktacular1701e who gives a shit

[@FreneticZetetic]

I always felt like MM4 was the first one that actually progressed the gameplay fully. I've personally loved the slide and charge shot, and the earlier games feel incomplete to me without them. I'm also that weirdo that likes the latter three entries on the NES the best! Great content as always.

[@ButtaMilkBiscuitsGaming]

now sliding on mega man 1 and 2 would be a feat

[@ishdx9374]

seems rather hard to fit in even 5 game genie codes

[@Kuikkamies]

The Charge Shot became a Mega Man mainstay for its basic versatility and no game in the series should've gone without it. Why? As mentioned in the video, the level layouts have to take into account. While not making the game harder per se, a properly implemented Charge Shot level design would put enemies into positions where a well-made blast could save the day, but at the same time, creative level design would make different stages take Special Weapon utility into notion. The Buster was always an underpowered weapon, and giving a charging capability made the player feel more powerful, more in-control. At the same time, it is a completely optional add-on. While a skilled player can negate the use of most Special Weapons during a run, to most people the Special Weapons still offer far more utility. Much like Sliding, Dashing and the Triangle Jump, Charged Shot was ultimately a core addition to give the player more options in offence and mobility, but sadly, out of these Charge Shots went rather underutilized, par Mega Man (World) 5 on the GameBoy. In no game do the enemies react differently whether or not Mega Man has a charge or is shooting the Charged Shot, something that could've brought much-needed dynamics to the play decisions. It was a great addition that never had the fine-tuning outside it deserved (outside MM4 and 5 on the GB.) That said, giving a look at the two aforementioned GB games might be of interest.

[@postplays]

I have a request: I had a game genie as a child and I played it with a lot of games. One of those games being Mega Man 2. In the Game Genie booklet in the MM2 section it has a warning: "NOTE: all codes make the music sound strange. It's harmless." I've always wondered why that is. Maybe you can do a video on that? Would be interesting. Thanks.

[@RT55J]

IIRC the Game Genie writes to the NES's sound hardware's "sweep" registers for the sound effects in its menu (the sweep registers can change the sound of the notes somehow). Mega Man 1 and 2 (a) do not use the hardware sweep registers in their music and (b) do not initialize or write to those registers at any point, so they end up using the Game Genie's modified values rather than the default values. Thus, the music sounds weird. There are actually .nsf rips of those soundtracks that have this mistake built into the files. It's great. (Someone else can correct me if I got something wrong.)

[@postplays]

@@RT55J thanks for the response.

[@_polpon]

Nice creative solution to use BNE to branch always because you loaded $#64 before it. I like those kind of solutions :)

[@Metaldetectiontubeworldwide]

Nice videos you make , althought am a fresh noob ..lol But coded in the late '80 my MSX 2 .. Still working and in my living room as display ..lol Grtz from the Netherlands Johny geerts

[@thiscoolaccount4488]

So cool! As a beginner I feel like I juuuust barely know enough about programming and the different base numeral systems to make it through the video, so your explanations were great

[@Yakushii]

T R I G G E R E D The opening screen has MM4 and MM5 switched!

[@DisplacedGamers]

All I can do is lol at this point. Ha! Apologies.

[@Yakushii]

@@DisplacedGamers Alright, trigger has passed. The video was really good. By the way, you mention that your way of finding the relevant mem addresses is a brute force way. What are the more, shall we say, elegant ways of doing it? Are there any?

[@DisplacedGamers]

@@Yakushii While I haven't done it in Mesen, using a watch/trace for a certain value, taking action in game, and then looking to see which of the previously found values changed can help zero in on a limited number of RAM address candidates. For example - you have three lives in a game, you search for a value of three, you die, search for a value of two, and see what RAM address(es) had those two values in common.

[@tehberral]

"and a fully-charged blue streak" Me: "...SPEEEEDS BYYYY! SONIC THE HEDGEHOG"

[@twistedsoul]

Too fast for the naked eye!

[@onetouchtwo]

I was binging your channel the other day so waking up to this is like a gift from teh g0dz. Great work!