How to Beat the Heart for the First Time [Defect Guide]

Core strategy for beating the Heart

The basic Heart strategy that applies to all characters is:

・Be able to consistently gain 30+ Block within at most 3 turns

・Set up high-damage attacks as early as possible (how early depends on your deck)

The Corrupt Heart gains Strength at fixed intervals.

The longer the fight goes, the more absurd the damage becomes—so you can’t win by chipping away little by little. +50 Strength is hell.

You need to slam in a huge burst of damage.

Also, on turn 2 the Heart will either use a “●×12 multi-hit attack” or a single heavy-hitting attack.

For this turn-2 attack, it’s okay to take it—even if you lose a big chunk of HP.

Use that window to create a state where you can either Block every turn or output extremely high damage every turn.

Next are some tips for beating the Heart with Defect.

Tips for Defect vs. the Heart

When fighting the Heart as Defect, keep the following in mind:

◆In most cases, build a defensive deck centered around Frost Orbs

◆Play 4 or more cards (effects) per turn

・Increase Energy and draw

　・Use 0-cost cards as your main attacks

　・Leverage Echo Form (a power that makes the next card trigger twice)

If you do, your win rate will improve.

Next, I’ll introduce decks that are easier to clear with, along with deck examples.

They’re listed in order from easiest for beginners.

Beginner-friendly decks

Focus deck

For beating the Heart, this is the most beginner-friendly archetype.

A deck that increases the buff “Focus,” which powers up Orbs—raising the damage and Block values provided by your Orbs.

Example game plan ▼

・Maintain Frost Orbs with cards like Recursion, or Evoke them frequently to keep your Block up, while Evoking a carefully-grown Dark Orb to finish.

A single 500-damage hit isn’t just a dream.

・Evoke Frost Orbs and Lightning Orbs every turn to secure steady Block and damage each time.

Once you’re used to it, getting around 30 Block & 30 damage every turn is no big deal.

Beginner-friendly ways to gain Focus ▼

・After increasing Orb slots with “Capacitor,” “Inserter,” etc., use “Consume” to gain Focus.

・Use “Biased Cognition+” as a finisher※ by jumping straight to +5 Focus

※If you play a debuff-immunity card like “Core Surge” or “Panacea” and then activate “Biased Cognition,” you can get +5 Focus with no downside.

Deck example (beginner-friendly) ▼

A deck that uses Panacea to negate Biased Cognition’s downside and stack Focus (Echo Form was picked up but not used※—more on Echo Form later).

Generate Dark with Doom and Gloom, and Frost & draw with Coolheaded.

Keep triggering Frost and Dark via Recursion and Loop.

Use Coolheaded, Machine Learning, Skim, and Foresight as draw sources.

Leverage Equilibrium to retain key cards, and use Charge Battery and Madness for Energy.

With the extremely strong anti-Heart relic “Tungsten Rod,” this clears comfortably.

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Deck example 2 (for those with some experience) ▼

A deck that increases Focus with Consume, protects itself with Frost, and fights with Lightning.

Increase Orb slots with Capacitor ×2.

Generate Frost with Coolheaded and Glacier, and generate Lightning rapidly with Static Discharge ×3.

Because Static Discharge requires taking damage, heal back up with Self Repair.

Supply the Energy needed to set up Frost and Static Discharge with Recycle.

Use Madness to make draw cards cost 0.

Dark Shackles is your safety charm for the Heart.

Claw deck

The second beginner-friendly archetype.

This uses the 0-cost attack card “Claw.”

By playing lots of Claws in a single turn, you create an ultra-high-damage 0-cost attack.

At first glance it looks like a bad match with the Heart’s “Beat of Death (take 1 damage each time you play a card),” but…

・Because they’re 0-cost attacks, it’s easy to build infinite combos
・The picks are simple—you don’t need to overthink it

…which makes it a beginner-friendly archetype. Also, the author likes it.

A more detailed explanation is here ↓

「鋭い爪（爪）」解説・運用の注意点この記事ではSlay the Spireのプレイアブルキャラクター「ディフェクト」のカード『鋭い爪（Stem版「爪」）』の解説をまとめて...

Deck example ▼

A short-burst deck that keeps adding Claws while securing draw with Streamline, Scrape, Coolheaded, and Hologram (it ended in 4 turns… I think).

Supply Energy with the relic “Nuclear Battery,” plus Recycle and Charge Battery, and basically cycle Claws via Scrape.

Honestly, if you find “Scrape” in Act 1, I think it’s fine to go all-in on this type of deck.

※Note: this isn’t a very standard approach. A Focus deck is more common.

Deck example 2 ▼

A deck that uses the relic “Sundial” to create an infinite combo and stuffs in Claws nonstop.

Use Fission and Reboot to assemble your hand, then use Madness to reduce cards like Coolheaded and Sweeping Beam to 0-cost.

Remove unnecessary cards with Recycle.

Whenever I see Sundial or Madness on a Defect run, I get hyped.

Decks for players who are getting used to Defect

Next are archetypes for players who are getting comfortable with Defect.

These are decks built around the super overpowered card “Echo Form.”

Echo Form deck

A deck that uses the “cheat” card that makes the first card you play each turn trigger twice.

・Play Echo Form within 2 turns
・Prepare a high-damage attack

If you can accomplish those two points, you can win even without much synergy in your picks. It’s that strong.

However, you do need to properly remember card effects and enemy patterns—in other words, a certain level of piloting skill is required.

Deck example 1 ▼

A “play-by-the-situation” mishmash deck with no clear synergy—except it has Echo Form.

To survive until Echo Form comes online, pick plenty of Frost cards like Chill, Glacier, and Coolheaded.

Use Compile Driver? (No—) Use Aggregate (gain 1 Energy per 3 cards in your draw pile) for Energy. Aggregate is strong.

Then you can double Coolheaded for 4 draw and rock-solid Block.

Or use Buffer for 4 turns of no damage.

A deck that makes you feel like you can’t possibly lose.

Deck example 2 ▼

A deck that repeats the loop:
Energy → play Echo Form & Meteor Strike → Energy → draw → Meteor Strike → repeat.

While managing your hand with Equilibrium, block with Go for the Eyes, Charge Battery, Leap, and Genetic Algorithm.

Retrieve Meteor Strike with Skim and Rebound and fire it again and again.

Once you get Meteor Strike online once, it’s “my turn” forever.

The end.

How to Beat the Heart for the First Time [Defect Guide]