Slay the Spire is a 2019 roguelike deck-building game created by the American indie studio Mega Crit. The game was first released for PC by Mega Crit and later made available for home consoles and mobile devices by Humble Bundle. It was initially offered in early access for Windows, macOS, and Linux in late 2017, with a full release in January 2019. The game was later released for PlayStation 4 in May 2019, Nintendo Switch in June 2019, and Xbox One in August 2019. An iOS version came out in June 2020, and an Android version was released in February 2021.
In Slay the Spire, players try to climb a spire made up of many floors that are created randomly. Players choose from four characters and fight enemies and bosses as they move upward. Combat uses a system similar to a collectible card game, where players earn new cards as rewards from battles and other activities. Players must use deck-building strategies to create a strong deck that helps them succeed in climbing the spire.
Slay the Spire was highly praised and was nominated for several awards in 2019 and 2020. It is seen as the video game that helped start a trend of roguelike deck-building games. A sequel, Slay the Spire II, was released in early access in March 2026.
Gameplay
Slay the Spire is a roguelike deck-building game. At the start of a playthrough, the player chooses one of four pre-selected characters. Each character begins with a specific amount of health, gold, a unique relic that provides a special ability, and a starting deck of cards that includes basic attacks and defenses. Each character has cards specific to them that are added to their deck during the game. The goal is to progress through multiple floors of the Spire. Each floor has a branching path with encounters, including monsters, elite enemies that give better rewards, campfires for healing or upgrading cards, shopkeepers who sell cards, relics, and potions, chests with random items, and choice-based encounters.
Combat happens in turns. Each turn, the player receives a new hand of cards and three energy points. The player can use any cards as long as they have enough energy to pay for their cost. At the end of the turn, unused cards are placed in a discard pile. Cards vary by character but usually include attack cards to harm enemies, skill cards that help the player or weaken enemies, and power cards with effects that last until the end of combat. Each enemy shows what action they will take, such as attacking, blocking, or casting spells. Some cards or enemy attacks may add unplayable cards, like Wounds or Curses, to the player’s deck, which can make it harder to play effective cards. After their turn, the player can plan how to avoid damage. If the player’s health reaches zero, the game ends, and they must restart from the beginning. If the player defeats all enemies in an encounter, they earn gold and can choose one of three randomly selected cards to add to their deck. Other rewards include relics that give permanent benefits, such as more health or better card effects, and potions that can be used during any turn to heal or weaken enemies.
The game requires players to build their deck strategically using cards obtained from loot and relics. Too many weak or unplayable cards can make the deck less effective, so players must decide which cards to keep and when to remove others to improve their deck.
Slay the Spire includes metaprogression, where completed or failed runs earn points to unlock new characters, relics, or cards for specific characters. Up to 20 Ascension difficulty levels can be unlocked, each adding challenges like lower health or stronger enemies. The game has three standard acts, and an optional fourth act, Act IV, can be accessed by collecting three special keys. In Act IV, the player faces the final boss, the Heart of the Spire.
Achievements challenge players to complete tasks, such as climbing the tower using only a starting relic or with only common cards. A daily challenge lets players attempt to reach the highest floor under specific conditions with a fixed random seed, ensuring all players start with the same encounters. The custom mode allows players to adjust game difficulty with modifiers.
Development
Slay the Spire was created by Mega Crit, a game studio based in Seattle. Anthony Giovannetti and Casey Yano were the main developers. They wanted to combine the ideas of roguelike games, which are known for their random challenges and permanent failure, with deck-building games like Dominion. The game was also inspired by the Netrunner collectible card game, which Giovannetti enjoyed and for which he runs a community website. The game was built using the libGDX framework. This was chosen because Java, the programming language used, allowed the game to run on Windows, macOS, and Linux. However, Yano later had problems with the framework being broken by updates to operating systems and not supporting consoles well.
To test the game and get feedback, Giovannetti asked expert players from the Netrunner community to help. This was important for balancing the game’s difficulty, as the randomness of roguelike challenges and the card-based gameplay made it hard to set the right difficulty. By using many testers and tracking gameplay data, the developers found which cards worked well and which needed to be removed. For example, cards that were too weak were not chosen by players, while cards that were too strong appeared too often in winning decks. They did not worry about players finding powerful combinations, as the game was single-player and had no opponent to feel overwhelmed.
At first, enemies did not show their next action, which was common in most turn-based role-playing games. This design did not work well with the roguelike feature of permanent failure. During testing, players had trouble understanding card abilities without clear situations to use them. The developers first created a "Next Turn" system that let players choose targets to see their next action in the interface. This system added something unique to the game, according to Giovannetti, and allowed them to create new buffs and debuffs that were easy to explain. However, the interface had problems when multiple enemies were present. They later changed to the "Intents" system, which used icons to show enemies’ next moves. At first, the icons did not show exact attack numbers but used ranges based on different weapons. Giovannetti wanted to avoid overwhelming players with too many numbers, but testers found that having numbers made the game more engaging and helped players create new strategies. The way players progress through the spires with branching paths and random events was inspired by the game FTL: Faster Than Light.
When the game first released in early access in November 2017, it had two playable characters. More characters were planned for later during the early access period. Giovannetti said that having about 75 different cards per character was the right balance, as too many cards would make deck building too chaotic, a problem faced by Netrunner. Charlie Hall of Polygon noted that the game’s mechanics were already well-developed at launch and that regular updates made it more appealing to buyers. Giovannetti said that feedback from online streamers helped improve the game’s balance, as streamers often gave honest opinions without hesitation.
During early access, the game added more potions with unique effects and more events. On Steam, the game supports user-created modifications through the Steam Workshop, allowing players to design new characters, cards, monsters, and other items. The early access period ended on January 23, 2019, with the full release of the game. A fourth playable character was added as part of a free update, first released to Windows users on January 14, 2020.
Humble Bundle helped Mega Crit release the game on non-PC platforms. Slay the Spire was released for PlayStation 4 in May 2019, Nintendo Switch in June 2019, and Xbox One in August 2019. Mobile versions for iOS and Android were planned for 2019 but were delayed until early 2020. The iOS version was released in June 2020 and had the same features as the computer and console versions. The Android version was released on February 3, 2021. In July 2024, Humble Bundle shut down its publishing division, which meant Mega Crit could no longer support or update the mobile versions.
Reception
According to Mega Crit, the game's first early access release in November 2017 sold very slowly, with about 2,000 copies sold during the first weeks, a time when most games sell the most copies. Although the company shared access keys with streamers and influencers, these did not lead to many sales. Sales increased significantly after a Chinese streamer featured the game on their channel, which had over a million views. During the week ending January 21, 2018, Slay the Spire was the second highest-selling game on Steam. By February 2018, the game had more than 500,000 players, based on estimates from SteamSpy. Mega Crit reported that by the end of June 2018, sales of Slay the Spire had passed 1 million copies, and by March 2019, sales reached 1.5 million copies.
When the game was first released, it received positive reviews, with an average score of 89 out of 100 from Metacritic. OpenCritic reported that 98% of critics recommended the game. IGN named Slay the Spire as the Best Strategy Game of 2019, and PC Gamer gave it the Best Design award for 2019. Later, IGN ranked the game among the best 25 PC games of the past decade and listed it as one of the top 10 roguelike games.
Board game adaptation
In January 2021, Mega Crit announced they were making a cooperative board game version of Slay the Spire with Contention Games. The game includes over 730 cards and allows players to choose from four different characters. One important difference from the video game is that the board game can be played by four players working together. A crowdfunding campaign for the board game started on November 2, 2022, and reached its funding goal in just 6 minutes. The campaign raised $1.4 million (about $1.5 million in 2025) on its first day and finished with nearly $4 million (about $4.4 million in 2025) total. CBR added the game to their list of most anticipated tabletop games for 2023.
In September 2025, a crowdfunding campaign was announced for a reprint of the original board game and an expansion pack called Downfall. The expansion pack is based on a popular mod for the PC version of Slay the Spire with the same name. This mod lets players control the game’s bosses, who defend the Spire against the heroes.
Sequel
In April 2024, Mega Crit announced that a sequel to Slay the Spire, titled Slay the Spire II, would be released in early access in 2025. The game will include returning characters such as the Ironclad, the Silent, and the Defect, as well as at least two new characters: the Necrobinder and the Regent. The sequel will also add a cooperative play mode for up to four players. Mega Crit shared that the decision to create the sequel was influenced by strong fan support for the first game. They plan to release the sequel in early access so fans can help shape the final version of the game. Due to changes in the Unity engine licensing, Slay the Spire II will be developed using the Godot engine. In September 2025, Mega Crit delayed the release, later confirming that early access would begin on March 5, 2026.