Slay the Spire: Metrics Driven Design and Balance

In this 2019 GDC session, Mega Crit Games' Anthony Giovannetti discusses how the dev team approached balancing for Slay the Spire.
Register for GDC: ubm.io/2yWXW38
Join the GDC mailing list: www.gdconf.com/subscribe
Follow GDC on Twitter: / official_gdc
GDC talks cover a range of developmental topics including game design, programming, audio, visual arts, business management, production, online games, and much more. We post a fresh GDC video every day. Subscribe to the channel to stay on top of regular updates, and check out GDC Vault for thousands of more in-depth talks from our archives.

[@jonathandorozowsky4005]

I love how this dude briefly summarizes questions asked in Q&A before answering. Not only does it ensure everyone heard the query, but it gives the questioner a chance to clarify if necessary. I feel like it's somehow a living example of improvement via iteration and feedback.

[@9695tommy]

Fun fact: I always volunteer at GDC (I was at this talk and asked the 2 questions at the 26:53 mark), and we are always remind the speakers to repeat the question, mainly for audio reasons (it wasn't always the case that the actual questions are recorded). So not really an example of iteration haha but still nice for sure.

[@ocdashi5333]

16:27 "Players will naturally gravitate to the ascension level that make sense for them" no we will always play the top unlocked level and take our ass beatings thank you.

[@TheOnlyFeanor]

Yeah i THOUGHT I’d stick around 14/15 ascension max, because after that it’s just unfair. However, turns out I’m playing all 4 characters at ascension 20 with a heart kill try every single time. I love pain and suffering and low win ratios…

[@tomekk.1889]

​@@TheOnlyFeanor You're crazy

[@Bhit_Whyz]

@@TheOnlyFeanor I'm in the middle of doing the same minus the heart kill because there's no record of it haha. Gotta race the release of Slay the Spire 2

[@PetitAmiral]

Laughed out loud when I saw Corruption and Dead Branch pop out in the "warping" discussion :)

[@aenpien]

I was impressed by the balance of this game. It's cool to hear an explanation.

[@PurpleFreezerPage]

Ok I know this is random but the first thing that comes to mind for why I love this game is the speed of every action in combat. There's no Pokémon style slow attack animations - you can go PAP PAP POW WAM in 2 seconds if you want.

[@jonathandorozowsky4005]

Sound effects add a lot to that.

[@justsomeannoyingredpanda]

And there's even a speed mode to go even faster in case some found it too slow.

[@metalmonster9536]

"How do you manage emotional feedbacks?" "Delete it" they nailed it.

[@rubenzs3161]

One of the most valuable GDC talks for sure

[@ryanbrothers5377]

This is one of the most successful indie games ever, a true success story. Cool to hear from the dev.

[@benedict6962]

Max respect for everyone in that session. Good questions, good answers.

[@antondovydaitis2261]

It's extremely heartening to see competent and ethical development. Every programmer on Earth would do well to follow this role model.

[@hibryd7481]

They did such a fantastic job. I enjoy GDC talks conceptually, but most people have worked on games I haven't played or even heard of. But I've got 245 hours logged on STS. Love this game, best thing to come along in years.

[@samliveshere88]

250 hours later I absolutly love this game and still find myself going back to playing it

[@Bradbradhehe]

Awesome talk, always appreciated the way StS is balanced

[@RglMrn]

Incredible game and great talk. Thanks!

[@Bhit_Whyz]

It's interesting that some of the design processes they went through resulted in a default decision, with relics or mechanics that kept other iterations of the design in place. Like discarding your hand at the end of your turn is default, but they have Runic Pyramid and the retention mechanic to enable holding onto cards. The enemy intents are visible by default (but some are ambiguous, like buffs and debuffs), but Runic Dome reverts it to that random state. The whole balance between ascension difficulty and daily wackiness. A super interesting lesson in how to capitalize on ideas that can be situationally interesting, but not suitable for basic play.

[@yourMoonstone]

This is SO good!!! The insight here is immeasurably valuable as I'm working on my own card game. Thank you so much for uploading this and thanks to the Mega Crit team for sharing their process!

[@Bretinator]

How is it going, 2 years later? ;)

[@bluehome8193]

How is it going, 4 years later? ;-)

[@jMattMorians]

Awesome. I was just talking with my friends about the main strength of this game and here it is a video about it.

[@lukascook8477]

What a great talk!

[@MopeyN]

Bought this game 2 weeks ago (Switch release which I've waited for ages) and got 50 hours, so far. Excellent game, it has so many good different card game aspects. I didn't finish the video (yet), but as soon as it popped up as a new video on my playlist, I was smiling, already :)

[@MopeyN]

In case you cared: 6 months later, I'm around 220 hours of playtime in and at around Ascension level 10~11. I'm still playing. I'm still in love. Thanks for the thumbs up and kudos to you, guys!

[@kevinmoo9902]

cool bro planning on picking it up on the switch aswell

[@MegamanX195]

4 years later now: how long did you play for? Ever beat A20?

[@MopeyN]

@@MegamanX195 Funny you'd ask! In about a week, it'll be three years since I claimed 100% achievements in this game (yes, I marked my calendar for that 🥳). I played with each character up to and through A20 and had a really good (and frustrating, of course) time 😀 I accumulated more than 500 hours playtime

[@notrab13]

Fantastic talk.

[@Mattball82]

You and your partner made the best strategy game ever, sir, thank you 👍

[@yrussq]

Really nice talk!

[@mario_actually]

Great talk!

[@Lunareon]

Great talk, great game! Even if there's no actual co-op mode (yet?), it was a fun game to play with friends, just chilling out and making collective decisions. :)

[@solsystem1342]

There's a fun coop-ish challenge you can do. You have two people play on the same seed with different characters. Whenever you enter an event you must make the same choice, whenever you get card rewards you have to take the same card slot (ie both take left, middle, or right), and you must take the same path on the map. Basically, anything that happens in menus outside of battles and shops has to be done together. No other constraints apply in battles or in shops. Also, the real kicker. If one player dies the other must immediately abandon their run. We never made it very far but I'm sure better players could do a lot better. It's quite fun when you both get good cards and it's like "do you REALLY need to take the left card though? I'd kinda like an inflame on the right".

[@ahuman7027]

There is a mod now available on Steam, Together in Spire, you play the same fight, but choose your own reward

[@LaurentLaborde]

listening to it while playing slay the spire :)

[@SpaceDodo]

Thanks!

[@studiojavakhan9547]

Hellow ! I was wondering, what where the metric tools/library where you using ? (PS : Really love the game, still need to finish ascension level 20 on the defect)

[@CE-ot1ni]

That smirk and "no comment" when the co-op question came up... you know they gotta be working on it.

[@TZerot0]

I mean the game is based on netrunner, so something involving a second player has to have been considered from the start.

[@whatdothlife4660]

No

[@brucebrenneise430]

Ironic that Anthony mentions Bob Ross as an example of happy accidents and spontaneity when it's known that Ross painted 3 iterations of every painting he did for his PBS show. So, ultimately, further proof of the point being made here.

[@FinetalPies]

Dang, makes a great game and is a charismatic talker? Too good

[@quizzer]

My favourite game of the year.

[@Oscar-xt8hm]

I'm really curious of how they sort the feedback they received on discord

[@johnhobbes2268]

Slay the spire has one of the best adjusted fights that I've ever seen. For every powerful combo which is possible there is one enemy which is designed to counter this combo. (the death branch+ corruption combo maybe one of the few exemptions.) And it is a good game for ever statistic nerds :-)

[@lupeters213]

There is a curse card, which makes you lose 1 hp for every card played. The timekeeper heart boss only allows you to play 12 cards per turn. The heart deal damage to you for every card played.

[@sirhasslich536]

@@lupeters213 the punishment is incomparable to the advantage. Sure, these cases require you to play carefully instead of just picking a card any card, but the reward is way above the skill floor even there. Most of my heart kills were with a DB, even on other classes.

[@andrewg3196]

Excuse me while I go get 5 flexes and whirlwind

[@meathir4921]

24:20 I assume this means Creative AI?

[@Brodysseus113]

he didn't talk about MATH, I wanted MATH REEEEE

[@goncaloferreira6429]

6:09 same thing aplies to limited play mtg and the whole reason why cards have diferent rareties

[@MehYam2112]

Fantastic content and delivery, thank you. Also, looks like four viewers are stuck on A20.

[@MattyCakez18]

Picasso’s 500th iteration painting: Still wrong

[@IkomaTanomori]

31:15 - I recognize that voice asking the question! Hi Alexis!

[@miguelcampillos]

Hola Finn, espero que te guste el video :)

[@RDonSCom]

Who's asking the question at 25:00? It's such a familiar voice and it's bothering me that I can't pin exactly who it is.

[@MartinGP_3dfxlegacy]

Hello! What tool is Ascension? Thanks

[@austeyen5628]

ascension is their ingame difficulty level if thats what youre asking

[@jesusmcastillo8306]

Is it Yahtzee the dude who asks the question about "too many feedback"?

[@mohandasjung]

Just watched at 1.5x, its just like him!

[@denisbachman8159]

😎💪

[@orelyosif5852]

" *Every* card sholud have a place" *Setup crying intesefies*

[@eldritchemissary4718]

Sometimes you can set up an expensive card like nightmares or wraith form

[@solsystem1342]

Setup into finnaly (I think it's called. It's the silent card that does like 50 damage for free if but is only playable if your draw pile is empty) is completely busted when used in a cycling deck.

[@magnusjakobsson7163]

Was that Rami Ismail asking the first question?

[@mario_actually]

Magnus Jakobsson definitely not.

[@misomiso8228]

0:30 netrunner :-( F

[@marksmod]

telemetry... yess... hahah!

[@goncaloferreira6429]

so the game sold 1.5 milion copies? are these 2 guys set up for life?

[@pierrogus]

Yes

[@artificialbox]

i think EA could learn a lesson here

[@chuckm1961]

There is no “X” in the words “et cetera”.

[@IstyManame]

- "Let's talk about balance" - "the game is single player so we don't really care"

[@misterbeach8826]

it is interesting, of course, but bear in mind that slay the spire was unique when it came out. everything he said many other devs did too, i.e. subnautica, yet subnautica zero is a commercial fail with almost no active players... contrary to subnautica. what i'm saying is: IF you have a unique yet mainstreamy enough game to be commercially interesting, then it works. IF not, then all your data will not help you, even if you were successful before with another game and did 5 gdc talks about how clever you are.

[@jigartalaviya2340]

Unlike u at least they did something with their lives.Think about that.

[@mtaur4113]

ok but y shiv so bad

[@anazron805811]

*Sniffs, snorts, slaps lips together, breaths hard into mic* Great talk, but this video hurts me.

[@meathir4921]

He’s a developer, not a public speaker.

[@jaredarmstrong7403]

At least he’s not as bad as Zizek. My goodness.

[@desertwater8445]

First?

[@DavidGuild]

Talk was good. Constantly swaying back and forth, not so much.

[@meathir4921]

Why does that matter? Your eyes are meant to be on the power point and he’s not exactly a public speaker.

[@danikpri50]

Great talk!