
June 18, 2026
Building Infinite Loops in Slay the Spire
Lets shift your puny wombo combo brain into a stochastic sequence state brain without shedding too many tears.
I look at math a lot when playing this game. Here's a core idea I keep in mind.
Lets shift your puny wombo combo brain into a stochastic sequence state brain without shedding too many tears.
I'm going to tell you about an interesting game computer scientists are playing right now. And it will make a lot of sense when you think of it in terms of slay the spire.
They are trying to find busy beavers.
"The busy beaver game aims to find a terminating program of a given size that (depending on definition) either produces the most output possible, or runs for the longest number of steps" - Wikipedia
After you draw your first hand, what's the most number of cards you can play in a row without it being an infinite...
On the boundaries is often where we learn the rules of the world we live in.
Slay the spire is not a deck haver, it's a deck builder. You don't start with an infinite, you have to get there.
STS2 is built to have less infinites than STS1. STS2 also doesn't want you to permanently double something, and then do it again every turn.
Most games, we're not finding infinites. But we're still building towards them. We're building a deck that does more as we create it.
In STS, you get what you get. There's no such thing as a deck build because you can't guarantee anything will drop. We're going to take whatever is the next best option.
The goal is to balance this concept of extending a busy beaver play with also taking whatever you need to get through the next fight. It will never be perfect, but it might just win.
Here's a great example of busy beaver extension from the first 3 floors.
- Defect picks a random rare card reward from neow which is reboot. Reboot's initial addition to the deck means that one time during the battle, if we want to play an extra strike or defend that isn't in our hand, we can play what we have and then play the reboot and see if we draw what we need. Reboot is already useful and is creating slightly extended play when compared to the base deck.
- First fight reward we pick refract. Initial add to the deck is that it can do 18 to a single target and 8 aoe at the end of the turn. On the first few floors this can finish off most enemies that are at half health. With reboot, we can draw it more often.
- Second fight reward we get charge battery. Now a few sequences open up
- We play a charge battery. Next turn. we have 4 energy and draw a refract, play it, play a defend, have defense and refract. This is good enough for most fights
- We already have 4 energy from last turn. Our deck reshuffles, we play a charge battery and a refract. Our next turn is more powerful
- We play a charge battery, we now have 2 energy, we play a reboot because we don't have enough block, it reshuffles we get a charge battery and no refract. We play another charge battery. We have enough block this turn, we've taken 4 cards out of our deck of 16, next turn theres a 5/12 (close to 50%) chance to draw a refract and also have 5 energy which on fight 4 means close to full block if not full block.
- Theoretically if reboot never exhausted and you had a 3 card deck, reboot + charge battery + any damage card. You could play charge battery, reboot until you were out of energy, and double the amount of energy you had every turn until you had enough energy to fully block and play something like a single upgraded attack 100 times to do 600 damage. You can actually do that in this game. It's just really unlikely.
With the transition from the basic deck to our 3 card pseudo-infinite, you can see how we busy beavered our way there. And maybe you can see some of the sticky concepts I'm talking about as well.
The goal in play isn't to replicate my busy beaver. There's too much going on in this game to play that way. Instead your goal is to start to see them more often. Oh when I pick this card with this card it extends my play (kingly punch + deck manipulation). Ah, and with this relic it extends it even more (monkeys paw + echo form + creative ai = two powers and two 0 cost cards in my hand per turn).
Not what do I copy but how can I see what's already in front of me.
As someone who's beaten A10 beta branch on every character and A20+heart on two, this is an idea that I think about every day.