Poison Build — Slay the Spire 2 Build Guide

Stack Poison and let the fight end itself — the patient route that scales infinitely.

Poison — Inevitability

Play pattern: "you're really just a block deck." Poison needs no synergy to kill — one well-timed source scales to 450+ damage if the fight runs long — so the entire build question is how long you can survive. Priority one is defense: Footwork, Abrasive, Leg Sweep, Shadow Meld and Well-Laid Plans come before any Poison card.

Core cards:

Card	Cost	Effect	Why it earns a slot
Noxious Fumes	1	Poison every turn, passively	"The best inevitability": ~150 damage in 10 turns, ~450 by turn 20 — a full damage solve for one Energy; the upgrade roughly doubles how fast it kills
Snake Bite	2	Applies Poison (7; upgraded 10)	28 total damage unupgraded; take it highly in defensive decks
Bouncing Flask	—	Multi-apply Poison	A variant of Snake Bite that stacks
Deadly Poison / Poison Stab	—	Straightforward Poison application	Mediocre individually, decent once stacked — Poison scales with Poison
Aces	—	Poison application, and a Sly card	"Probably the best poison card because it's just free"
Corrosive Wave	—	Poison scaling	Named among the cards that can single-handedly kill a boss if the fight goes long
Burst	—	Doubles the next card's effect	Burst into Bouncing Flask or Snake Bite: 9 Poison becomes 18 — roughly four times the total damage
Exhumer	—	Catalyst-style Poison multiplier	"Speeds up the clock so fast" — hard to slot until your deck has enough Poison
Bubble Bubble	—	Late Poison payoff	Only good once Poison is already stacked — effectively free with Noxious Fumes; the one Poison card not to take early
Blur	—	Retains Block into next turn	Situational survival tech for the long game
Mirage	—	One-time Block scaling with Poison	Fine in a pinch against bosses, despite the Exhaust

Relics: the material recommends no specific relics for Poison — the build lives or dies on Block cards, not relics.

How to pilot it: survive first, poison second. Block with Footwork-stacked Dexterity, drop Noxious Fumes, and let the triangle numbers work; supplement with Burst lines. The fight should go long — that's the plan, not a problem.

Strengths and weaknesses: the most reliable scaling in the game for long fights, and it asks nothing of your deck's other cards; it's simply slower than Sly, which is why the video ranks it third without calling it bad.

Related

• Silent build hub — all archetypes overview
• Builds Overview
• Silent card table
• Card Tier List