ITEM DUPLICATION in my Mario Maker?!?!

Family Friendlier: • dupC
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[@CarlSagan42]

SCUBA is an acronym for Self Contained Underwater Breathing Apparatus. What you may not know is that Tuba is also an acronym for...Terrible Underwater Breathing Apparatus

[@eeeeee8762]

Amazing

[@Cqat1]

Get well (:

[@PieMan061]

I can’t breathe 😂

[@Mothuzad]

I did know that, thanks to r/jokes last night 😅

[@harpritsandhu9105]

Gaper

[@tomsoyer6195]

How blind can you get? Carl: "Hold my beer" (He didn't see he was alone in the room)

[@Brass319]

That's why we have all those psas to tell you not to drink and play mario

[@star14604]

Can’t wait for meta to evolve into the level saying, “yes hidden block.” Then into not having one

[@kirikotone]

Just have the hidden blocks be at the goal containing 1-ups this way it won't even be a lie and it would be funnier.

[@star14604]

@@kirikotone so they search for it to just have it at the end great idea

[@bobby4tw]

🤣🤣🤣

[@a3wagner]

Carl: If only I could hit an on/off switch, I could jump up here Carl, while sitting 2 inches away from a switch: maybe the 1up does something? Carl, still not seeing it: aha, I can slip through these 2 pixels around the spiny. Surely this is it

[@a3wagner]

[@AbruptAvalanche]

All of the seemingly useless 1-ups in the first level are actually there to teach you the different koopa mechanics needed for the key duplication glitch. That whole level is brilliant!

[@Maximo2204]

It's amazing how Carl can be really brilliant when solving complex puzzles or using weird mechanics, but still gets completely stuck by just missing obvious doors or conveyor belts

[@daniielah.7569]

It's the power of ADHD

[@arohk4415]

For him, every Level is a dark level.

[@AidanWR]

Carl really hyperfixated on 1UPs doing something for him in levels that show no signs of using 1UPs to solve anything

[@jessevanstraaten4111]

0:57 The trickery is doing it's thing. It made Carl blind 😲

[@PopYTP]

bold of you to assume he wasn't already blind

[@CarlSagan42]

What's weird is I've watched 2 other people play this level and both didn't see the door for some reason...

[@mintegral1719]

@@CarlSagan42 Honestly, I didn't see the door either, even just watching you play it... blindness is apparently an epidemic

[@PopYTP]

@@CarlSagan42 HOW

[@jessevanstraaten4111]

@@CarlSagan42 I didn't see the door myself actually....

[@GummieI]

That last level is actually really impressive, having 3 different, but intermingled path through the level, depending on the powerup state, can't have been easy to design

[@ThomasWinget]

Four, wasn't it?

[@ajpiskel]

@@ThomasWinget Yeah, it was four and the design wasn't too complex. Each vertical gate pretty much only allowed one type through at each section, so it was very controlled. I'm not sure i'd call it metroidvania because you can only go forward and you're not doing a whole lot of exploring. Always just go right, basically.

[@PieMan061]

Yeah tbh, I was a little shocked how underwhelmed/uninterested he sounded while playing it. Every time he unlocked something new, he just went “oh, ok” but in other puzzle/troll levels he goes wild on the design.

[@CarlSagan42]

@@PieMan061 I was just tired zzzzzz I usually try not to play levels while tired so as not to have people interpret it as you have here, but I was hoping I'd wake up and that was the time I had to stream for the day~

[@Grimmtombobulus]

It wasn't 😅 not my best work though. There's a better version of the same concept on my maker profile called Mario Joins Anonymous

[@Ytschi]

the "please drop a muncher on my head" in a lovely puzzle level just said everything we need to know (and love) about Carl

[@jurakarok3343]

Carl: This frog suit is too fast, it's control is awful Also Carl: Hasn't let go of run since picking up controller

[@LinkNinjaMaster]

Funny how apparently nobody on chat told him to just stop pressing the Run button for a second

[@FSSZilla]

I thought the same thing! It's a Mario game, most players have been trained for decades to hold the run button at all times.

[@omlett6482]

Troll level makers seeing any niche tech showcased in a fun and entertaining level: "We could make a horrible anti out of this"

[@TheBBmTV]

Carl the recent consistent flood of uploads is giving my brain the good feelings, glad you're around to make my internet more enjoyable.

[@ruggedlemmings9163]

Carl: *gets to the end of a great puzzle level* "Oh please drop a muncher on me!" Remember kids: not all levels end with a troll. :^)

[@Juniper_Rose]

Carl getting stumped by non-puzzles is my favorite genre of Carl Brain't

[@clarafedde8674]

*watches Carl play Mario maker for years Carl: "Can you kill ghost with shells?" *facepalms All things Carl has learn:

[@turbo8628]

That last level was one of the best designed mario maker levels i have seen. I love it when the point of the level is to break parts of it down to find alternate paths. Something about the efficiency of it is very pleasing.

[@OKIGorgon]

23:20 I love how Carl changed over the years. He now wants horrible anti-softlocks, but at the begining of SMM2 he was banning people for making them.

[@wizulus]

BAHH!!! Soooo cool to see that glitch level here :). I tried setting up a key thruplication puzzle but my brain exploded.

[@CarlSagan42]

hahahahaha amazing

[@inthefade]

With three koopas?

[@pkinsect6618]

The way I understand the exploit, I don't think it would be possible to get a third key. Indeed, at any given time, you can only have two koopas holding a key at the same time on screen: one that was carried through the door (because mario can only carry one object at a time), and one that just spawned (I don't see why the game would spawn more keys than one during a reload). Thus, you can only get two keys during a single "reload", so if you were to get three keys, you would need to get one of them before the reload, but that will prevent the "spawning one" from appearing again so that's not possible

[@TrevorD19]

Get Ryu to play your level.

[@wizulus]

​@@pkinsect6618 It would have been with a checkpoint and required death to reset the keyling, but it felt like garbage so I stopped :D

[@emaximus93]

Flashbacks to that video in which Carl said "Jizzman" instead of "Jimzan" multiple times... God, that was beautiful.

[@Earthboundmike]

Carl caused me so much pain in that first level, good god man. THE OVERCOMPLICATION IS SO REAL.

[@Earthboundmike]

That being said getting to the solution was some good work

[@eliminoh_p7877]

It’s very dangerous to show Carl new glitches and tech.

[@TheAdvertisement]

Those music levels are so cool, the original platform and music genuinely just makes this feel like its own indie game.

[@Maximo2204]

I'm incredibly disappointed by the fact Carl never even thought that in order to do more fine movements with the frog suit underwater, all he ever had to do was release the damn "run" button... He was holding it the whole time and wondering why he was always moving so fast

[@kylestewart2829]

The way Carl describes the level: at first kinda slow then they it grew on me is exactly how I felt about Carl. Which can be really frustrating sometimes but I still love you Carl

[@RibomRibom]

I like how the koopa behavior is determined by the shell. It's like the shell is its external brain

[@Meteorite_Shower]

This only proves that no matter how well designed and indicated your levels are, _someone_ isn't going to get it. (yeah yeah, I know Carl was tired at the time)

[@eduguerrero6601]

Once again Carls blindness gives me incredible amounts of anxiety

[@nyaaguy354]

this is the third time carl has a level that includes transforming koopa persoanlitys with diffrent couloured shells and he still had to learn it from scratch every time xD

[@toolebukk]

Mario Maker is 7½ years and MM2 is soon 4 years old! I cant believe we're still seeing so many awesome new levels! What an amazing game!

[@wellshit9489]

25:50 editor flexing and Im here for it

[@davethelizard1463]

Lol just using the good ol' music muscle

[@wellshit9489]

@@davethelizard1463 it's very impressive, where do you work out?

[@freekingsweet666]

Ah just what I need, some Carl coming in my eyes.

[@cloudedcrow8822]

Umm…. Phrasing??? Maybe?

[@DareDevil_00I]

Could probably have worded that better

[@janko1]

🤨

[@dariogamboa5912]

📸📸📸📸📸📸

[@MacroscopicMicro]

*vine boom*

[@RobertStoll]

I'm surprised no one has managed to crack MM2 and reverse engineered the source code at this point.

[@inthefade]

Or do arbitrary code execution

[@M_Alexander]

Every time he calls the Koopa Troopa a Koopaling I'm just 😣

[@shaoronmd]

key duplication would be an interesting way for dev exits

[@larrylazer]

I was having similar issues with the DPad back when I was playing Celeste several years ago. I wound up switching to the Stick halfway through my play through of the game and I’ve stuck with using the stick ever since. It’s a whole lot more precise.

[@bluestar2059]

In before someone (probably Carl, let's be honest) makes a level where the main gimmick is smuggling one koopaling all the way across the map for some key duplicating shenanigans. Like, a "getting over it" level, but you have to bring this koopa with you (which you have to keep tossing up to reset, otherwise it reactivates in your hands and kills you).

[@augustociciliati8382]

*First level starts off kinda empty.* CarlBlind42: "Oh, there's a door?"

[@facelessguru]

"What on earth does that spring do?" Actively kicks respawning shell over and over again

[@nebulae5236]

Hearing Carl rant about the switch D-pad reminded me of playing some of my first Celeste grandmaster maps where I dual-wielded left stick and D-pad on the pro controller. It’s hard to master but it does get consistent, so don’t give up on the D-pad yet!!

[@LychkovIA]

for some reason I absolutely love the way Carl said "coins" at 0:20, LOL

[@TheAdvertisement]

Love how cooldown levels are just a thing now. Also lmfao they're really finding every way to break Mario Maker aren't they?

[@mortalkombatworld9707]

key is stored in the balls

[@ntedeschini]

"YOU CAN DUPLICATE KEYS" Yeah, a keymaster can do that, Carl

[@JUNKO____]

Looks like we've reached that "any new tech/glitches discovered are literally game changing" part of this MM's life cycle.

[@TheSkepticSkwerl]

There are definitely some levels where key duplication would bypass so much. For example. Redcoin level where a key is in a koopa hidden behind a key door to a red coin. You'd have to possibly do that room twice. But 1 room twice would beat 6 rooms

[@jk560]

The poison mushroom level went from a sucky level to a awesome level really quick

[@Demigod2Tet8]

It would be really cool making a level where you have to use this tech to get two keys, but after the first key-door there's a contraption that kills you if you have a key, then after that there's the second key-door. So the idea would be that you have to delay getting the second key by carrying the original koopa in a swapped shell all the way through the first key-door and past the anti-key-checker2000™ and only kill that koopa once you actually get to the second key-door.

[@dhaxiskhadhammer]

I thought maybe Carl was trolling not seeing the first door. His blindness knows no bounds.

[@pkinsect6618]

Here's my understanding of the exploit in the first level. It seemingly all boils down to a very weird behavior with koopas: 1) when reloading a room, to know if the koopa will respawn, the game checks whether mario is holding the corresponding *shell* : if mario is holding the shell pointing to this koopa it will not respawn, otherwise it will 2) when reloading a room, to know if a spawning enemy needs to hold a key or not, the game checks whether its key has already been obtained; in the case of koopas, it checks whether mario has already killed the corresponding *koopaling* Moreover, you need to add to this a specificity of mario: 3) if mario goes through a door holding an object, this object is *not* respawned per se, it is kept as is. With this, we can understand the exploit as follows: before entering the door, carl kicks the koopaling holding the key out of its green shell, and makes it go into the red shell (by the way I don't think avoiding killing the green shell was important at this point, contrary to what Carl thought). The state of the game is then: mario is holding a red shell, with a koopaling inside of it holding a key. When mario goes through the door, by 3), mario is still holding a red shell with a koopaling with a key. Additionally, mario is not holding the shell of the green koopa, so by 1), it respawns. Finally, the key corresponding to this green koopa has not been obtained yet (equivalently, the koopaling has not been killed yet), so by 2), it respawns holding a key. And that's why we have two keys at the same time. Some remarks: - the reason this works only with koopas is precisely because 1) and 2) check different things. For a galoomba for instance, it couldn't work, because mario has no way of transporting the "key inside the galoomba" without either collecting it (which, by (2), would prevent the key from respawning) or carrying the galoomba itself (which, by (1), would prevent the galoomba from respawning altogether) - one key comes from the fact that mario "carries it" through the door, and the second one comes from the way the room spawns. Consequently, I really don't think it would be possible to get a *third* key, because you can only get one key from spawning (two keys cannot spawn during the same reload, and once you collect one of the keys, the "spawning key" won't reappear on the following reload), and one key from carrying (mario can only carry one object at a time through doors). - there is a specific case where a koopa (or an enemy in general) is not allowed to respawn when reloading the room, even if mario is not holding it: it is when there is a clear condition about killing this enemy, and mario has already killed it beforehand. I wonder how a clear condition on koopas would interact with all this mess

[@coreycreehan8197]

the Sean Hip puzzle with this tech is gonna be BONKERS lol

[@Nimilphex]

It's no wonder creators keep trying to put Carl in a box, otherwise they have to Carl-proof their levels!

[@FaeCherry]

Carl; damn there’s no way in that box. Me; but the door Carl; no way in, maybe I’ll throw the shell into the void. Me; DOOR

[@scrantondangler8068]

Carl asking a benevolent musician, who makes interesting levels for some *Evil* is fitting for the evil mechanics mastermind.

[@whynotanyting]

I completely missed the door at the beginning myself, don't worry Carl

[@DarkKen87]

The thumbnail in the beginning is from Link's quest for ass. Jeez I haven't watched that in forever lol

[@RexRath]

The koopaling is stored in the balls.

[@alemangioni]

What a beautiful surprise this new video for is! ❤

[@iTZBLaSToFFTiMe]

"If only I had an On/Off Switch," he said while ignoring the On/Off Switch in a box and getting stuck in a level for far too long. You're no good for my blood pressure, sir.

[@AkumaAPN]

Does anyone remember which video it was when Carl was playing a level, and near the beginning it looked like an N for NO, but then he jumped down, and the screen scrolled, and it said NYES, and then NYESNT ?

[@michaelhodnett431]

The game just busted wide open again.

[@TheJadeFist]

24:30 Carl is so focused on the mushroom he forgot he's in a shell that can be hit with the spring.

[@shmendrickswamii5914]

Mario-troid-vania? And Früg Mario latches on to the heavy, heavy block with sticky feet and skips it across the surface like a stone. Less running on the top, more Früggy version of "dolphin moonwalk".

[@ZaneIsHere]

OMG that last level reminded me way too much of this one particular game from the GMTK 2019 Game Jam called Level1_1, it's literally the same concept but with Mario Maker and I cannot believe that it was executed really well in an MM2 level, really well done! Here's the link to a brief description of Level1_1 if you wanna take a look: kzbin.info/www/bejne/pV66o4RtbN-IrKM

[@facade11663]

If I had to guess it's track loops on an on/off Y that drops onto another loop to create stages of note blocks dropping into the "play" loop

[@XperimentorEES]

I'm speculating it's a memory issue, by that I'm guessing whatever mario is holding is stored separately from the level when going through a door/pipe, so when you refresh/reset the level the game doesn't check what he's holding, maintaining the carry-able duplicate while the one left on the level is wiped.

[@seronimo__7735]

25:50 Yes Dave!!!!!!

[@davethelizard1463]

Hell yeah!

[@badradish2116]

koopa escort by juggling shells... BRILLIANT

[@mabelsilva1995]

35:38 fart flower light baby! throwback omfg

[@le_gus001]

27:47 Maan, that's that hot TikTok song called I should not be here!

[@felicityc]

carl is overthinking walking around in this one, christ

[@CarlSagan42]

"trickery" puzzles need to be overthought because the simple solutions are never correct, thus the point of naming them "trickery" -- this particular maker was quite generous leading you to the solution but most do not at all.

[@felicityc]

@@CarlSagan42 damn i got owned

[@markfeuchter2051]

33:14 we still need to SHHHHHIT!

[@bluehax6]

I get why he's saying koopaling but it isn't any less painful

[@TheLich43]

It's made even worse because he conditioned chat into saying it too

[@kuroblakka]

50:49 Bro got the Tom ass scream

[@Polygonetwo]

I can't wait to annoy everyone by saying "Hin't" instead of goodbye.

[@dipdinger]

There is no doubt in my mind that he was going to lose the frog suit immediately after he got it. That thing looks tough unless you practice

[@MazaBLaze]

I've been stuck on this damn level for days!

[@BerniPro]

the amount of carlblind in this video has reached a new Climax...

[@matthewhutton8275]

I suppose it would have made it too obvious (even though there's a hint at the end) but I'm disappointed it wasn't called 2 Keys, 1 Koopa.

[@Schenkel101]

TIL keys are stored in the koopaling

[@Holyballsinhell]

What would have happened if you tried to reverse-smuggle the key ? From green to red then taking the green key but then using the red one that has a duped key to dupe it back into the green one ? I feel like there's further testing required Larl :D

[@justwingingit8110]

If this mirror were clearer, I'd be standing so blind

[@TheAlexdodd]

This is some ultimate Carl Blind today

[@logicfoxgaming1411]

That key duping is some… weird tech. I mean it makes sense from a coding standpoint. Rule 1: Keep track of which Koopa has the key even if it enters a new shell. Rule 2: If a koopa enters a different shell, it becomes the Koopa that owns the shell. Those rules don’t mix. Huh. It’s an incredibly simple yet deceptive oversight. I’m not surprised it wasn’t caught by Nintendo. This stuff is why Mario Maker 2 isn’t actually broken. You should just never hand out the keys to a level editor. This would never happen in a proper game.

[@jondo7680]

So the Koopaling has the key and the shell controls if it respawns. Both would need to be tied to the same to prevent the duplication.

[@jondo7680]

Oh yeah, he got that too. But he can't see the door lol

[@cowboyclip]

22:09 perfectly on beat transition!

[@pekkatuna3965]

It look like water pipe level have speed run like a nintendo speed run challenge

[@Avalarion87]

that setup of the hint can be used in a troll level

[@SJrad]

oh man so many levels are gonna be cheezed

[@gagglegames]

11:27 that look of wonder

[@robinw2096]

22:30 this music slippity slizaps

[@TFGRhinehart]

It's okay, Carl, I didn't notice the door either.

[@intyente9824]

"if i pounded that dude" - Carl Sagan 2023 "I could hit that, but i dont think it will help me" - Also Carl 15 seconds later in 2023

[@SpaceLobster21]

Oh man these levels were so cool, loved this!

[@sophiegrey9576]

the tf2 economy is in shambles now that we can dupe keys

[@karanoelle4819]

Only Carl can take a semi linear multi run level and turn it into a puzzle. Man is too into trolls and puzzles he's lost track of what normal levels look like.

[@diractirpitz84]

Sees carl miss obvious door. ...THIS is the real how it feels to be 5Dum level XD. great vid.

[@Andaisdet]

So that koopa key duplicate could be used in troll levels to bypass key checks with locked doors I mean like, if you’re not supposed to have a key, and if you go through the key door you die, you can carry the key in the shell to avoid being forced to activate the key door

[@yomi-xg9zv]

Hi Carl can you get the world record on that key duplication puzzle

[@jhsevs]

53:35 I DID NOT KNOW ABOUT THIS TECH 😧😧 is it possible to do in the original smb3 too?