Slay the Spire: Downfall board game expansion adapts a fan-made video game mod

The Downfall expansion raised $3.8 million on Kickstarter in just three days

Contention Games founder Gary Dworetsky raised nearly $4 million with his 2022 Kickstarter for Slay the Spire: The Board Game, which turned 2019’s genre-defining rougelike deckbuilder into a cooperative tabletop game. Now, Dworetsky is adding more variety to the experience with Downfall, a tabletop expansion based on the fan-made video game mod of the same name that has already raised $3.8 million since launching on Kickstarter on March 24.

“I feel like a lot of board gamers were apprehensive about a video game adaptation, and they have good reason to be, because [video game adaptations] don't have the best track record with people outside their core audience,” Dworetsky told Polygon in a video interview. “But we've gotten a good reputation with people in the board game community, and it's bringing new players in and they, in turn, try the video game. I think Slay the Spire 2 is going to accentuate that even more as it has co-op.”

The original board game simplifies a lot of the math-based mechanics from the video game, and it balances play for parties of up to four players. The Downfall mod introduced a new hero character, the Hermit, and a new gameplay mode where you control bosses defending the Spire. These characters are all very complex, so Dworetsky had to come up with creative solutions to make them work while maintaining their unique flavor.

“The most challenging has actually been the Hermit,” Dworetsky said. “There’s this central mechanic called Dead-On that you can activate if it's in the middle of your hand physically. We knew we didn't want to make people do that in the real world. They'll put their hand down and lose track.”

It took 15 iterations to get the mechanics right, with Dworetsky playtesting the character at conventions before deciding on Rapid Fire, where effects are more powerful based on how many cards the player discards.

“We have the benefit of a lot of player knowledge and feedback at this point, so that has definitely influenced things,” Dworetsky said.

In Downfall, players choose between exploring the dungeon as heroes or taking on the role of dungeon bosses trying to defend the Heart. Dworetsky considered making a new board to reflect the different progressions, but eventually decided against making Downfall a standalone expansion. Instead, players will be able to mix and match characters as they eventually face either the Heart or the whale-like creature Neow.

“The only thing that might be strange is if you end up fighting yourself, because in Downfall, the bosses are the player characters,” Dworetsky. “If that feels odd to you, you can just reroll the boss.”

Dworetsky reduced that dissonance by changing the appearance and fighting styles of the hero characters. The Ironclad appears demonic and becomes fully corrupted partway through the fight, initiating a phase change with new abilities. The Silent looks like a witch and fights alongside its doppelgänger. The regular and elite monsters will stay the same, but Downfall also introduces plenty of new potions, relics, and events.

“We want player decisions to be more divergent and stretch people in different directions,” Dworetsky said. “The feedback we got is that people really like events where each player chooses a different option. We're adding another one of those events for each act, and some other events that you might recognize for the video game that weren't adapted before.”

The choice of characters will strongly influence the options and items players want as each has a very different playstyle. The Slime has slime cards that can be leveled up, letting you create an army of little buddies that will do damage on their own. The Guardian can switch between two modes at the start of each turn based on whether the player wants to focus on attacking or defense. Its cards can be enhanced by socketing gems, which is done through a set of special sleeves. The Hexaghost has a heat track that advances to empower cards and it also has abilities based on how many cards they’ve exhausted during a fight.

Licensing for Downfall was much trickier than for the base game because it was created by a large group of designers and artists.

“We were like, ‘How much do you want for this license?’ and they're like, ‘Nothing, it's a fan mod. We don't do this for money’ and I'm like, ‘I appreciate that, but we are selling the board game, and we would like to pay you,’” Dworetsky said. “They needed to hear it from a few different people to really accept that.”

The Kickstarter campaign for Slay the Spire: The Board Game - Downfall and a reprint of the original board game runs through April 9. The game is expected to be delivered in April 2027.