Should I upgrade Coolant in Slay the Spire 2?

Compare the upgraded text: At the start of your turn, gain 3 Block for each unique Orb you have.. If the upgrade lowers cost, adds damage/block, or enables a combo piece, it is usually high priority.

What builds use Coolant?

Coolant appears in 1 tracked build: Permafrost Bastion (A-tier, core card).

What character uses Coolant?

Coolant is tagged as a Defect card. See the Defect build hub for archetypes that care about it.

Updated for Data 2026-03-17Early Access — numbers may shift with patches.

Coolant

Defect · Power · Rare · 1 cost

Base

Upgraded

Card text

At the start of your turn, gain 2 Block for each unique Orb you have.

Coolant+

At the start of your turn, gain 3 Block for each unique Orb you have.

Builds that use Coolant

Archetypes that draft this card in real runs, with the role it plays.

APermafrost BastionDefect · Core card

Build context

See the Defect build hub for archetypes that feature this card in real runs.

Related cards

Coolant FAQ

Should I upgrade Coolant in Slay the Spire 2?: Compare the upgraded text: At the start of your turn, gain 3 Block for each unique Orb you have.. If the upgrade lowers cost, adds damage/block, or enables a combo piece, it is usually high priority.
What builds use Coolant?: Coolant appears in 1 tracked build: Permafrost Bastion (A-tier, core card).
What character uses Coolant?: Coolant is tagged as a Defect card. See the Defect build hub for archetypes that care about it.

Patch history

SpireForge snapshots card text from Untapped exports dated 2026-03-17. When Mega Crit ships a balance patch, we re-run the scraper and refresh every affected URL—see /patches for the editorial log.