Slay the Spire 2 Keywords Guide: Every Mechanic Explained

Why Keywords Matter

Every keyword in Slay the Spire 2 represents a mechanic that changes how cards behave. Knowing what they do isn’t enough. You need to understand how they interact with each other, which characters use them, and when they matter in a run. This guide covers every keyword in the current build.

New Keywords in Slay the Spire 2

These are the keywords that didn’t exist in the original game.

Sly (Silent)

When you discard a card with the Sly keyword, it plays itself for free instead of going to the discard pile. The card’s full effect triggers without costing you energy.

This changes how you evaluate discard effects. Normally, discarding a card is a cost. With Sly cards in hand, discarding becomes a way to play extra cards for free. Abilities like Calculated Gamble or Acrobatics that force discards become engines for free Sly triggers.

Why it matters: Sly turns the Silent into a character that can play 7-10 cards per turn with only 3 energy. The ceiling is very high, but it requires specific discard enablers in your deck. Without them, Sly cards are just normal cards.

Doom (Necrobinder)

Doom stacks on enemies. When an enemy’s current HP drops to or below their Doom value, they die at the end of the next turn. This is an execution mechanic, not extra damage.

The distinction matters. Doom doesn’t deal damage. It sets a kill threshold. You still need regular damage or chip to bring an enemy’s HP below the Doom line. But once you do, the enemy is guaranteed dead regardless of how much max HP they started with.

Why it matters: Against high-HP enemies and bosses, Doom means you don’t need to deal the full HP total in damage. You need damage plus Doom to exceed their current HP. This makes the Necrobinder uniquely good at ending fights against tanky targets.

Forge (Regent)

Forge is the Regent’s resource for creating and upgrading the Sovereign Blade. Each point of Forge improves the Blade. The Blade exists as a separate weapon outside your deck, and its power is cumulative. Forge gained in one turn stacks with Forge from previous turns.

Why it matters: The Sovereign Blade is free damage that scales every turn. In long fights, Forge builds create inevitability. The Blade will eventually outdamage anything the enemy can do. The question is whether you survive long enough.

Synchronize (Defect)

Synchronize provides a temporary Focus spike for the current turn. All orb effects (Lightning damage, Frost Block, Dark damage) are amplified during the turn you play a Synchronize card.

Why it matters: This is a burst tool, not a permanent buff. You use Synchronize on the turn where you need maximum orb output, either to burst down an enemy or to generate massive Block against a big incoming hit. Mistiming it wastes the spike.

Eternal

Cards with the Eternal keyword cannot be removed from your deck or transformed. They’re permanent. The most notable Eternal card is Ascender’s Bane, the Curse you start with at Ascension 5+.

Why it matters: Eternal cards change your deckbuilding math. You can’t trim them, so you have to work around them. Extra draw and exhaust effects that can target Curses help mitigate Eternal cards. But some Eternal cards are beneficial and you’d want to keep them anyway.

Returning Keywords

These exist in both the original and the sequel. If you played Slay the Spire 1, you know these. If you didn’t, here’s what each one does.

Exhaust

When a card is exhausted, it’s removed from your deck for the rest of the current combat. It goes to the exhaust pile, not the discard pile, and you won’t draw it again.

Exhaust is a cost on some cards and a benefit on others. Ironclad has an entire archetype built around exhausting cards for bonuses. Exhaust also thins your deck mid-combat, making your remaining draws more consistent.

Key interaction: Some relics and cards trigger effects when you exhaust a card. The more exhaust triggers you have, the more valuable each exhaust becomes.

Retain

A card with Retain stays in your hand at the end of your turn instead of being discarded. You keep it for next turn.

Retain is simple but powerful. It lets you hold defensive cards for turns when you expect big damage, or save a key attack card for the right moment. Cards with Retain are almost always worth picking because the flexibility they give you is enormous.

Block

Block is damage prevention. When you gain Block, it absorbs incoming damage before your HP takes a hit. Block resets to zero at the start of your next turn unless you have a relic or effect that preserves it.

The math: If you have 12 Block and take 8 damage, you lose 8 Block and take 0 HP damage. You have 4 Block remaining. If you take 15 damage with 12 Block, you lose all 12 Block and take 3 HP damage.

Block is the primary survival mechanic. Every character needs Block cards. Even aggressive decks need enough Block to survive turns where they can’t kill everything before the enemy acts.

Vulnerable

An enemy with Vulnerable takes 50% more damage from all attacks. If an attack deals 10 damage, a Vulnerable enemy takes 15. This is one of the strongest debuffs in the game.

Why you want it: Applying Vulnerable on turn 1 makes every attack you play for the rest of the fight 50% more effective. A single Vulnerability application can represent 30-50 extra damage over a full combat. Always have at least one source in your deck.

Weak

An enemy with Weak deals 25% less damage with their attacks. If an enemy would hit for 20, they hit for 15 instead.

Why you want it: Weak is the defensive counterpart to Vulnerable. Reducing incoming damage by 25% every turn is equivalent to gaining a significant amount of Block for free. Against enemies with multi-hit attacks, Weak is even more valuable because it reduces each hit.

Frail

When you have Frail, you gain 25% less Block from cards. A card that gives 10 Block only gives 7 with Frail active. Some enemies apply Frail to you.

How to deal with it: Frail makes your Block cards worse, not useless. You can still Block, it just takes more cards to fully cover an enemy’s damage. Removing Frail (through certain potions or card effects) is high priority when it’s applied to you.

Intangible

While Intangible is active, all damage you take is reduced to 1. A 50-damage hit becomes 1 damage. This is extremely powerful and extremely rare.

Why it matters: Intangible turns lethal turns into survivable ones. Cards or relics that grant Intangible are almost always top-tier picks. But it usually only lasts one turn, so timing matters.

Innate

A card with Innate always starts in your opening hand. No randomness. You draw it on turn 1 guaranteed.

Why it matters: Innate is valuable on setup cards that you want to play immediately. A scaling card with Innate starts working from turn 1 instead of whenever you happen to draw it.

Status Effects and Conditions

Beyond keywords on cards, there are conditions applied during combat.

Strength — Increases your attack damage. Each point of Strength adds 1 damage to every attack. Ironclad scales primarily through Strength.

Dexterity — Increases your Block gained from cards. Each point of Dexterity adds 1 Block to every Block card played.

Focus (Defect) — Increases the effectiveness of orb effects. Higher Focus means Lightning orbs hit harder, Frost orbs Block more, and Dark orbs charge faster.

Poison (Silent) — Enemies with Poison lose HP equal to the Poison amount at the start of their turn. Poison decreases by 1 each turn but doesn’t go away until it hits zero. Stack it high and let it tick.

Early Access Note

The keyword list is current as of the patch ~0.98.x build. New keywords may be added and existing ones tweaked as the game progresses through Early Access. The core returning keywords (Block, Exhaust, Vulnerable, Weak) are stable. Newer character-specific keywords like Sly, Doom, Forge, and Synchronize are more likely to see adjustments.