Mechanics

Resources

Health

Hit Points (HP): If you run out of HP, you die.

The most fundamental resource. HP can take any value from 0 to the player's maximum HP. HP is depleted by taking damage, and may be replenished at Rest Sites, between acts, or with any number of healing effects.

Max HP can be raised or lowered by various cards, relics, and events. Increasing max HP will also increase your current HP by the same amount.

Read more about Health.

Cards

Each character comes equipped with a starting deck of 10 or 12 cards. Cards are played during combat.

Outside of combat, they may be added, removed, upgraded, or transformed. Some cards or relics can also upgrade cards mid combat.

Read more about Cards.

Upgrading

Upgrading cards makes them more powerful. Cards can only be upgraded once.

Read more about Upgrade.

Transforming

Transformed cards become a random card of any rarity.

Read more about Transform rules.

Gold

Money Pouch: Shows how much gold you're carrying. Gold is the currency within the Spire.

Obtained from combat rewards, Events, Chests and certain relics/cards. Can be spent at the Merchant and certain Events to make purchases.

Read more about Gold.

Potions

Use potions during combat to gain bonuses or hinder enemies.

Single-use consumables that persist across combats.

Read more about Potions.

Keys

After a run has been won on Ironclad, Silent and Defect, an icon of 3 empty Keys appear to the left of the player's name. To access Act 4, all 3 Keys need to be collected in the same run. They do not have to be collected in the same Act.

• Ruby Key: Can be obtained at a Rest Site by clicking the Recall action, instead of Smith or Rest (or Lift, Dig and Toke) at the same fire.

• Emerald Key: Can be obtained by fighting a "super" elite, indicated by a burning animation on a map. Once the Emerald Key is obtained, super elites won't show up in later Acts.

• Sapphire Key: Can be obtained at any Chest instead of the Relic in the chest. Will not appear if N'loth's Hungry Face is active. Will only be linked to the bottom Relic if Matryoshka is active.

Trivia: These three keys appear in the game Dead Cells and unlock an outfit resembling the Ironclad.

In Combat

Card Piles

There are three piles in which cards may reside when not in the player's hand.

• Draw Pile: The pile from which cards are drawn at the start of the turn. The draw pile is populated at the start of combat with all the cards from the player's deck. Attempting to draw a card when the draw pile is empty triggers a shuffle (see below).
• Discard Pile: The pile to which most cards are sent after playing. When a shuffle is triggered, all cards from the discard pile are shuffled into the draw pile. Certain cards do not enter the discard pile after being played: Exhaust cards instead enter the exhaust pile, while Powers cards disappear entirely.
• Exhaust Pile: The pile in which cards that have been Exhausted reside. There is no way to recover cards from this pile, except with Exhume.

Certain enemies have attacks that shuffle Status cards into the discard or draw piles. Player cards may also shuffle cards into the discard pile (e.g. Overclock) or draw pile (e.g. Alpha).

Hand

The hand is where cards reside after drawing and before playing. During their turn, players may play cards from the hand, so long as they have the Energy to do so.

Hand Size Limit

The maximum number of cards allowed in hand is 10. There is no way to exceed this limit. Any draw action that would result in more than 10 cards in the player's hand will result in the remaining cards entering the discard pile immediately. Similarly, anything that creates cards, whether a relic (e.g. Dead Branch) or another card (e.g. Blade Dance), will send excess cards to the draw pile, so that the hand size limit is maintained at all times.

Turns

Combat is turn-based: first the player takes a turn, then the enemy party takes a turn, then repeat. This continues until either the enemy or the player dies.

Player Turn

At the start of the player's turn, three things happen:

1. Energy is set to the base energy (default 3), and
2. A number of cards are drawn (default 5), and
3. Start-of-turn effects trigger.

The default behavior can be changed, typically by Relics (e.g. Fusion Hammer increases the base energy by 1; Snecko Eye increases the number of cards drawn per turn by 2).

During their turn, the player may play cards or drink Potions. Cards with an energy cost will subtract that energy from the total. All player actions are resolved immediately upon being performed.

When the player presses End Turn, two things happen:

1. End-of-turn effects trigger.
   • This generally resolves in the order relics -> buffs -> cards (e.g. Orichalcum will trigger before Plated Armor, which will trigger before Burns).
2. Cards in hand are shuffled into the discard pile.
   • This will not occur with Runic Pyramid or any cards that are Retained, unless they are cards with end-of-turn Effects like Regret or Burn.
     • Cards with end-of-turn Effects can sometimes also be Retained at exactly 1 point: during the Awakened One phase shift. If Awakened One's first phase is killed with an effect that takes place right after the player's turn ends, but before the enemy turn begins (Defect's   Lightning Orb passive or Stone Calendar), cards that would normally be discarded like Burn can be Retained.

Then the enemy party takes its turn.

Enemy Turn

Enemy actions during their turn are governed by their Intents, visible as floating symbols above their heads. In multi-enemy encounters, enemies always take actions from left to right.

Outside Combat

Acts

Slay the Spire is split up into 3 acts: The Exordium, The City, and The Beyond. Each act is 17 floors long and has certain features in common, such as a Boss encounter at the end. An optional fourth act, The Ending, is unlocked after beating the game once with each of Ironclad, Silent, and Defect (see Keys).

Read more about Acts.

Floors and Floor Types

After completing any mandatory objectives, such as defeating enemies or choosing an option at an Event, the player may proceed to the next floor using the Map interface. Only floors ("nodes") that are connected to the current floor with a dotted line on the map can be accessed. Each floor may be one of seven different types.

Read more about Map Locations.

Chests

See Map Locations for all possible rooms.

Chests are objects which contain some amount of Gold and a Relic. Chests are only obtained through killing bosses, or encountering Treasure Rooms.

Boss Chests offer a choice of three different Boss Relics. You can choose to skip this reward.

There are three types of Non-Boss chests: Small, Medium and Large. Each has a different chance to give you a Relic and some amount of Gold.

Chests

	Small	Medium	Large
Spawn Chance	50%	33%	17%
Relics
Common	75%	35%	0%
Uncommon	25%	50%	75%
Rare	0%	15%	25%
Gold
Chance	50%	35%	50%
Amount	23-27	45-55	68-82

Small Chest

Medium Chest

Large Chest

Boss Chest

Other

Ascensions

Runs get harder as you win... (Winstreaks are unaffected).

See a list of Ascension modifiers here.