Unlocks Guide#

The Binding of Isaac has 34 playable characters in total — 11 in the base game, 23 added by later DLC, of which 17 are the Tainted characters new to the Repentance DLC. This page lists each character’s unlock condition and starting loadout, and explains the Completion Marks and the final achievement Dead God. For per-character gameplay details see the Characters Guide; for Tainted mechanics see the Tainted Characters Guide

Two Kinds of Unlock Conditions#

Character unlock conditions fall into two categories, farmed in completely different ways:

• Stat-based — “hold at the same time” a certain resource up to a set amount, e.g. Magdalene checks heart containers, Cain checks coins, Lazarus checks Soul Hearts. These conditions require beating no boss; enter a new run, stack the number, and the unlock triggers
• Action-based — defeat a specific boss, complete a specific chapter, perform a specific action, e.g. Judas requires beating Satan, Eden requires completing Chapter 4. These follow the normal completion flow, and the pace is set by your progress

Unlock Conditions Overview (Base Game, 11 Characters)#

The table below lists base-game unlock conditions and starting loadouts. “Hold at the same time” conditions read the character’s live values at that moment — heart containers and Soul Hearts carry across floors; you only need to hit the threshold at any instant, not within a single floor

A few easy-to-fumble points:

• Eve and Samson are mirror conditions — Eve checks “no red hearts picked up”, Samson checks “no damage taken”. These two get swapped all the time; remember: keep your hands off hearts for Eve, keep your blood intact for Samson
• Blue Baby’s 10 Mom’s Heart kills accumulate across runs — each run counts one kill; no need to chase multiple kills in a single run
• The Lost’s unlock depends on the Missing Poster — how to obtain the poster itself follows in-game behavior; once you have it, enter a Sacrifice Room and die on purpose; Sacrifice Room mechanics are covered in the Sacrifice Room Guide

DLC Character Unlocks (6 Characters)#

DLC unlock conditions range wider — from within-a-run boss fights to cross-run donation grinds:

Notes:

• Lilith is tied to Greed Mode — Azazel’s short-range Brimstone excels against Greed Mode’s dense trash mobs, making him the popular pick for farming Ultra Greed; see the Greed Mode Guide
• Keeper’s 1000 coins is a cumulative total — no need to donate it all in one run; accumulate slowly across runs — the safest but most time-consuming character unlock
• How to reach Mega Satan follows in-game behavior — the unlock condition itself only requires defeating him; how to get to his room is a routing matter

Tainted Characters (17)#

The 17 Tainted characters all unlock the same way, but each one must be done individually:

• Play the corresponding regular character to the Home floor
• Use the Red Key to open the hidden room to unlock that character’s Tainted version
• The Red Key itself is an item that must be unlocked first — how to unlock it follows in-game behavior
• You must use the matching regular character — e.g. unlocking Tainted Cain requires regular Cain to open the hidden room; other characters won’t work
• Per-character mechanics and strategies for all 17 Tainted characters are in the Tainted Characters Guide

Completion Marks#

Unlocking a character is just the start — every character also has 7 boss Completion Marks to earn:

• Mom, Mom’s Heart — the two main-story endpoints
• Satan, Isaac — the Devil route and Angel route endpoints
• Blue Baby (???), The Lamb — the Chest and Dark Room endpoints
• Ultra Greed — the Greed Mode endpoint
• Marks earned on Hard mode display as gold stars — distinguishing them from normal mode
• Once a character’s marks are all collected, a matching Trinket unlocks

Dead God#

Dead God is The Binding of Isaac’s 100%-completion final achievement — the full set of Completion Marks for all 34 characters is the biggest long-term chunk of it, with items, trinkets, challenges and more stacked on top. For endgame planning see Endgame Content

Clearing Up Common Misconceptions#

Many unlock conditions circulating online are outdated or garbled — the table below corrects the easiest ones to trip over:

Unlock Order Recommendations#

Ordered by how actionable each condition is — unlock the stat-based characters you can farm immediately first, then grind toward action-based and long-term goals:

FAQ#

Further Reading#

• Characters Guide — every character’s starting loadout and playstyle
• Tainted Characters Guide — mechanics and advanced play for all 17 Tainted characters
• Greed Mode Guide — the stage for unlocking Lilith and Keeper
• Sacrifice Room Guide — mechanics related to unlocking The Lost
• Endgame Content — long-term planning for Completion Marks and Dead God