Challenges

Challenges are unique runs in the game. Isaac typically starts each challenge with one or more specific items which make normal play more difficult. With few exceptions, Treasure Rooms are not available during challenges. Each challenge unlocks new content for the game, such as Runes, when completed.

General Strategy

Most challenges are designed to increase the difficulty of the game in a unique fashion. This doesn't mean all challenges are difficult, however; challenges like Computer Savvy are quite easy to beat. Some challenges do compensate for this by being especially punishing; Solar System is a good example of this. Each challenge has certain strategies that can be employed to make the run easier. However, there are a few strategies that can apply to all challenges.

• Challenges can be played in co-op, allowing a second player to contribute to the run without being hindered in the same way Isaac is. This is especially useful in any challenge where Isaac is Blindfolded, as the second player will be allowed to fire tears normally.
• Due to the lack of Treasure Rooms, Devil Rooms become much more valuable. Some challenges can be made much easier by making just one deal, but it is worth noting that other challenges reduce Isaac's health to an extent that Devil Deals become too risky.
  • Some rooms (including Crawl Spaces) may have Treasure Room items by default. Since these items are random, results can vary from run to run.
  • Because locked Treasure Rooms won't spawn, keys can be used far more liberally. In addition, Trinkets and Items that generate more coins, along with upgraded shops, can help Isaac acquire a greater range of powerful items.
• The BibleUpon activation, Isaac gains flight, allowing him to pass over all obstacles in the current room. Instantly kills Mom, Mom's Heart, and It Lives when activated, but will kill Isaac when activated while fighting Satan. instantly kills Mom and Mom's Heart / It Lives. All challenges require defeating Mom, and most require defeating Mom's Heart or It Lives, making this an extremely powerful item, especially in challenges where Mom or Mom's Heart / It Lives is the final boss.
  • Pandora's BoxUpon use, spawns certain pickups or items depending on the floor it is used on. Single-use. will spawn The Bible if used in Womb II, Utero II, or Scarred Womb II, making it a reliable way to acquire The Bible.
• Curse Rooms can spawn items, making them valuable.
• In some challenges, Dice Rooms and the D4Rerolls all of Isaac's items. are very useful, allowing that challenge's starting items to be rerolled, thus removing most of the difficulty. NOTE: This changes depending on the challenge. Most challenge pages contain details on the results of rerolling.
  • Butter!Using an active item will drop it onto a pedestal on the ground. Taking damage may result in dropping a passive item. can also remove starter items.
• Blindfolded challenges are arguably the most difficult challenges due to Isaac's inability to fire tears. There are several methods to work around this.
  • Familiars can provide an alternative method of dealing damage. Powerful familiars like Daddy LonglegsDaddy Long Legs' shadow follows Isaac and stomps on enemies., Lil' BrimstoneA Familiar that shoots a thin Brimstone beam. Must charge like Brimstone before shooting., and IncubusA demonic familiar that follows Isaac and shoots tears identical to Isaac's in terms of damage, range, fire rate, and effects. are therefore highly useful items.
  • The BoomerangThrows a short-range boomerang which does a bit of damage and has a high chance to stun the enemy for 2 seconds. Can also be used to grab pickups., The CandleThrows out a blue flame that can pass over gaps (but not through rocks). The flame damages anything in its path., and Red CandleThrows a persistent flame that deals high damage and diminishes as it damages enemies or blocks shots. are also useful for blindfolded challenges, since they recharge based on a timer, rather than an amount of cleared rooms.
  • ClickerTransforms Isaac into another random character. can allow Isaac to change into Lilith, whose IncubusA demonic familiar that follows Isaac and shoots tears identical to Isaac's in terms of damage, range, fire rate, and effects. overrides the Blindfolded effect by default.
  • Some spacebar items like Tammy's HeadShoots 10 tears in a circle around Isaac, which retain the damage, shot speed, and special effects (such as poison) of Isaac's tears. can be really helpful, providing alternative method of dealing damage.
• ChaosChaos causes items to be chosen from random item pools. When picked up, drops between 1-6 random pickups on the floor. is a powerful item in challenges, as it can allow powerful items to be found more commonly, such as in the Shop or after defeating Bosses.
• Defeating a boss beyond the specified end of the challenge (e.g. defeating Mom's Heart when the goal is to defeat Mom) will still spawn the trophy.
  • In some longer challenges (e.g. XXXXXXXXL), using a Sacrifice Room until it teleports Isaac to the Dark Room is a viable strategy. Once in the Dark Room, the trophy can be spawned by defeating The Lamb.

Notes

• Apart from the achievement related to beating the challenge, all achievements are locked. Also, no Donation Machines will appear in any challenge.
• The Challenge reward will not be unlocked unless the trophy is picked up. If a Devil Room or Angel Room appears allowing Isaac to go to Sheol or the Cathedral, the unlock will be forfeited.
• Isaac will not start any challenge with The D6Allows Isaac to re-roll collectible items in the current room into other items, depending on the current room's Item Pool..

Challenges List

Name	Conditions	Goal	Unlocked by	Unlocks
1. Pitch Black	Isaac Curse of Darkness Curse of the Unknown : yes : no		Default	Rune of HagalazComplete challenge #1
2. High Brow	Isaac Starts with: Number One+1.5 tears, -17.62 range E ColiGives "Turdy Touch" Effect. Enemies that touch Isaac are changed into poop. Butt BombsGives +5 bombs and makes all bombs Butt Bombs that fill the room with gas, damaging and confusing all enemies. Flush!Changes all enemies in the room into poop. Does not work on all enemies (Knights and bosses are immune). Instantly kills Dingle, Dangle, and Brownie. Petrified PoopGreatly increases the chances of a pickup dropping when destroying poop. : no : yes		Default	Rune of JeraComplete challenge #2
3. Head Trauma	Isaac Starts with: Tiny PlanetRange up and makes shot tears revolve around Isaac until they drop. Soy MilkTears shrink and do much less damage, but fire in very rapid succession. The Small RockIncreases damage by 1, increases tears by 0.2, and decreases speed by 0.1. Iron BarIncreases damage by 0.3 and adds a chance to shoot concussive tears, causing enemies to walk around randomly. : no : yes		Default	Rune of EhwazComplete challenge #3
4. Darkness Falls	Eve Starts with: PentagramIncreases damage and increases the chance for a Devil or Angel Room to appear. Dead BirdSpawns a flying familiar for the current room that chases enemies whenever Isaac takes damage. Whore of BabylonIncreases damage and speed whenever Isaac has half a red heart or less (one red heart for Eve), ignoring any soul or black hearts. Razor BladeUpon use, deals one heart of damage to Isaac and grants +1.2 damage for the current room. Sacrificial DaggerDagger orbits Isaac, dealing very high damage. Dark MatterIncreases Damage by 1 and adds a chance to shoot fear tears. : no : yes		Defeat Mom's Heart 11 timesDarkness Falls	Rune of DagazComplete challenge #4
5. The Tank	Magdalene Starts with: InfamyChance to block projectiles coming from any direction. Bucket of LardGrants two empty heart containers and heals Isaac by half a heart, but decreases speed by 0.2. Thunder ThighsDestroys rocks upon contact with Isaac. Adds one heart container and lowers Speed. Yum HeartRestores 1 whole red heart. : no : yes		Have 7 or more heart containers at one timeThe Tank	Rune of AnsuzComplete challenge #5
6. Solar System	Isaac Blindfolded Starts with: Distant AdmirationA red attack fly circles further out than the Halo of Flies / Pretty Flies, but closer than Forever Alone. Deals more damage than Forever Alone. Forever AloneSpawns a blue attack fly that orbits a long distance from Isaac. Halo of FliesSpawns two pretty fly familiars that block enemy shots and deal contact damage to enemies. TranscendenceGrants flight. : no : yes	/	Defeat Mom's Heart 3 timesSolar System	Rune of PerthroComplete challenge #6
7. Suicide King	Lazarus Starts with: IpecacReplaces tears with explosive and poisoning projectiles fired in an arc from the mouth. Mr. MegaGives Isaac 5 bombs, and makes all dropped bombs larger, which have an increased blast radius and increased damage. My ReflectionGives Isaac's tears a boomerang effect, and increases range and shot speed. 1 random pill : no : yes		Defeat Mom's Heart 11 timesSuicide King	Suicide KingComplete challenge #7
8. Cat Got Your Tongue	Isaac Blindfolded Starts with: Guppy's Hair BallLoosely follows behind Isaac. Can be swung like a flail by rapidly spinning Isaac in a circle. Grows bigger by killing enemies. Guppy's HeadSpawns 2-4 blue flies to damage enemies. Guppy's TailIncreases chance of finding gold chests and normal chests, but reduces chance of finding pickups. : no : yes		Become Guppy (Collect 3 Guppy Items)Cat Got Your Tongue	Rune of AlgizComplete challenge #8
9. Demo Man	Isaac Starts with: Dr. FetusTears are replaced by bombs that benefit from bomb-enhancing effects and slide for a fixed time after being fired. Remote DetonatorBombs you place explode only when you use this item. Gives 5 bombs. Match StickIncreases the chance of Bombs dropping after clearing a room, and the chance of finding Bombs when opening a Chest. : no : yes	/	Defeat Mom's Heart 9 timesDemo Man	Chaos CardComplete challenge #9
10. Cursed!	Magdalene Starts with: Blue MapShows secret and super secret room locations on the map. The CompassReveals all special rooms (except secret rooms of any kind). Raw LiverGrants 2 Heart Containers and completely restores health. Treasure MapReveals all rooms for every floor. However, it does not reveal icons or secret rooms. Yum HeartRestores 1 whole red heart. Child's HeartIncreases the chance of a Heart dropping after clearing a room, and the chance of finding a Heart when opening a Chest. Curse of the Cursed : yes : yes		Have 7 or more heart containers at one timeCursed!	Credit CardComplete challenge #10
11. Glass Cannon	Judas Starts with: Epic FetusIsaac's tears are replaced with guided missiles, like those used by the Doctor's Remote. Loki's HornsGives a random chance for projectiles to fire in all 4 cardinal directions. : no : yes		Beat challenge #19 and defeat Lokii for the 1st timeGlass Cannon	Rules CardComplete challenge #11
12. When Life Gives You Lemons	Isaac Starts with: 9 VoltReduces the charge of any Activated Items by 1. Any 1 charge items instead have timed recharges. HabitWhen Isaac is hit, 1 point of an item's charge is filled. Lemon MishapCreates a small yellow pool of creep, which damages enemies that cross it. 1 Lemon Party pill : no : yes		Default	Card Against HumanityComplete challenge #12
13. Beans!	Isaac Blindfolded Starts with: 9 VoltReduces the charge of any Activated Items by 1. Any 1 charge items instead have timed recharges. The BeanIsaac releases bad gas, poisoning any enemy in close vicinity. The Black BeanWhen taking damage, Isaac farts, causing poison damage to all enemies in range. Butt BombsGives +5 bombs and makes all bombs Butt Bombs that fill the room with gas, damaging and confusing all enemies. PyroAdds 99 bombs. : no : yes		Default	Burnt PennyComplete challenge #13
14. It's in the Cards	Isaac Starts with: 9 VoltReduces the charge of any Activated Items by 1. Any 1 charge items instead have timed recharges. The BatteryActivated Items can be "overcharged" to allow for an additional use. Deck of CardsGives Isaac a random Tarot Card. Starter DeckIsaac can hold 2 cards at once and all pills are replaced by cards. 2 random tarot cards : no : yes		Default	SMB Super FanComplete challenge #14
15. Slow Roll	Isaac Starts with: Cupid's ArrowGrants Isaac piercing tears that travel through enemies (but not obstacles) instead of breaking on impact with them. My ReflectionGives Isaac's tears a boomerang effect, and increases range and shot speed. PolyphemusMakes Isaac shoot one huge tear. Also reduces Tears to minimum. Damage increased . If tear does more damage than an enemy's life, the tear continues to travel with the extra remaining damage. : no : yes		Default	Swallowed PennyComplete challenge #15
16. Computer Savvy	Isaac Starts with: Spoon BenderGrants Isaac homing tears. TechnologyReplaces tears with a piercing laser with unlimited range. Technology 2Decreases damage and replaces right eye tears with a unlimited range, piercing laser which fires continuously. : no : yes		Default	Robo-Baby 2.0Complete challenge #16
17. Waka Waka	Isaac Starts with: Anti-Gravity-2 Tear Delay. Tears float in position until firing ceases, after which they will fly off in the direction they were shot in. Strange AttractorPickups, trinkets, and monsters are magnetically attracted to Isaac's tears. : no : yes		Default	Death's TouchComplete challenge #17
18. The Host	Isaac Starts with: The MulliganTears have a 1/6 chance of spawning allied blue flies when they hit an enemy. Spider BabyWhen hit, spawns up to 2 blue spiders. TickDrain 15% health of each enemy with more than 60 HP (ie. most bosses). Also restores one red heart of Isaac whenever he enters an uncleared boss room. The Tick cannot be swapped out for another trinket. : no : yes		Default	Technology .5Complete challenge #18
19. The Family Man	Isaac Blindfolded Starts with: BFFS!Increases the size and damage of familiars. Brother BobbyFollows Isaac around shooting normal tears. Dad's KeyOpens all doors in the current room when activated, including doors which require a key to open and entrances to secret rooms. Opens the big doors in the first room of both The Chest and the Dark Room. Rotten BabyA familiar that spawns blue flies. Sister MaggyA familiar that follows Isaac around shooting blood tears. : no : yes		Pick up both Key pieces from the Angels in one runThe Family Man	Epic FetusComplete challenge #19
20. Purist	Isaac : no : yes	/	Defeat Mom for the first timePurist	Rune of BerkanoComplete challenge #20
21. XXXXXXXXL	Isaac : yes : yes Every floor is the size of an XL Womb floor, but does not combine the floors of each chapter.	/	Defeat Mom for the 1st timeXXXXXXXXL	Gold HeartComplete challenge #21
22. SPEED!	Isaac : yes : yes Everything is sped up like the Broken Watch effect.	/ within 16 minutes, otherwise under constant periodic damage every 10 seconds.	Defeat Mom for the 1st timeSPEED!	Get out of Jail Free CardComplete challenge #22
23. Blue Bomber	??? Blindfolded Starts with: Brother BobbyFollows Isaac around shooting normal tears. Kamikaze!Creates an explosion in the same area as Isaac, dealing half a heart of damage to him and also damaging all enemies caught in the blast radius. PyromaniacIsaac heals 1 heart instead of taking damage from an explosive source. Adds 5 bombs. Mr. MegaGives Isaac 5 bombs, and makes all dropped bombs larger, which have an increased blast radius and increased damage. : no : yes		Destroy 10 tinted rocks and defeat Mom's Heart 11 timesBlue Bomber	Gold BombComplete challenge #23
24. PAY TO PLAY	Isaac Starts with: Money = PowerIncreases damage by 0.04 for every coin Isaac has, up to +3.96 damage at 99 coins. Sack of PenniesIsaac is followed by a small bag that drops a coin every 2 rooms. 50 coins : no : yes Every door costs 1 cent to enter. Isaac drops money when hit. Isaac dies if he run out of money.		Defeat Isaac as CainPAY TO PLAY	2 new pillsComplete challenge #24
25. Have a Heart	Isaac Starts with: Charm of the VampireHeals the character for half of a red heart for every 13 monsters killed. : yes : yes Pennies drop instead of red hearts. Many items that restore red hearts have no effect.	/	Defeat Mom for the 1st timeHave a Heart	2 new pillsComplete challenge #24
26. I RULE!	Isaac Starts with: The BoomerangThrows a short-range boomerang which does a bit of damage and has a high chance to stun the enemy for 2 seconds. Can also be used to grab pickups. Key Piece 1Combined with Key Piece 2, unlocks the golden gate in the starting room of The Chest and Dark Room to fight Mega Satan. Key Piece 2Combined with Key Piece 1, unlocks the golden gate in the starting room of The Chest and Dark Room to fight Mega Satan. The LadderAllows Isaac to walk across gaps one square across by automatically placing a ladder between the two walkable sections. Mom's KnifeIsaac's tears are replaced by a knife that pierces enemies, can travel through obstacles, and can hurt enemies while Isaac is holding it. Holding down the fire button before firing increases its range and power. Trinity ShieldIsaac gains a shield that protects him from enemy shots. : no : yes		Defeat ??? or The Lamb for the 1st time, and defeat Satan as IsaacI RULE!	Poker ChipComplete challenge #26
27. BRAINS!	??? Blindfolded Starts with: 3 Bob's BrainSpawns a familiar that charges forward when shooting tears and explodes upon contact with an enemy, damaging and poisoning them. The familiar respawns after a few seconds. Thunder ThighsDestroys rocks upon contact with Isaac. Adds one heart container and lowers Speed. : no : yes		Defeat Isaac 5 timesBRAINS!	Stud FinderComplete challenge #27
28. PRIDE DAY!	Isaac Starts with: 3 Dollar BillGives Isaac a random tear effect every room. The effect given changes upon entering a room. The effect changes every 3 seconds. Rainbow BabySpawns a familiar that follows Isaac around and fires tears with random effects. : no : yes Cannot drop or replace Rainbow Worm.	/	Defeat Mom for the 1st timePRIDE DAY!	D8Complete challenge #28
29. Onan's Streak	Judas Starts with: The Book of BelialUpon use increases damage by 2 for the current room and by a further +50% if the character also has the Blood of the Martyr. Guarantees a Devil Room or Angel Room will be open after beating a boss while holding it, or increases the chance by 12.5%. Chocolate MilkGrants charged tears that deal greater damage when fully charged. : yes : yes Missing a shot deals damage to Judas.		Defeat Mom for the 1st timeOnan's Streak	Kidney StoneComplete challenge #29 ( The unlock is bugged and actually unlocks Blank Rune)
30. The Guardian	Isaac Blindfolded Starts with: Holy GrailGrants flight and one heart container. Isaac's HeartIsaac himself is now immune to all damage, and a heart familiar appears and follows Isaac. If the heart is hurt, Isaac is hurt. Punching BagSpawns a Mulligan Familiar that will wander the room randomly. Enemies will attack the Mulligan if it's closer. : no : yes Isaac's Heart will follow Punching BagSpawns a Mulligan Familiar that will wander the room randomly. Enemies will attack the Mulligan if it's closer. instead of Isaac.	/	Defeat Mom for the 1st timeThe Guardian	Blank RuneComplete challenge #30 ( The unlock is bugged and actually unlocks Kidney Stone)
31. Backasswards	Isaac Starts with: 8-10 random items : no : yes All Chapters progress in reverse order, losing 1 item and 1 red heart container each floor ascended.	The Basement/The Cellar/Burning Basement I	Defeat ??? or The Lamb for the 1st timeBackasswards	Laz Bleeds More!Complete challenge #31
32. Aprils Fool	Isaac : yes : yes The minimap displays the floor's layout accurately, but displays Isaac's position inaccurately. Pedestal items and pickups are not what they appear to be. Active item, pill, card, and rune effects are randomized upon each use, making them very unreliable or deadly (for example Suicide King). Items with no charge time (i.e. How To Jump, IV Bag, etc) can be used repeatedly for random effects. Stoneys have a chance of being replaced by Cross Stoneys. Every boss is The Bloat. Isaac's health is not what it appears to be. Key and bomb numbers are accurate.	/	Defeat Mom for the 1st timeAprils fool	Maggy Now Holds a Pill!Complete challenge #32
33. Pokey Mans	Isaac Starts with: Mom's EyeshadowTears have a chance to charm enemies. : no : yes Each use of Friendly Ball causes a random monster to be spawned. Friendly Ball instantly charges once the spawned monster is killed.		Defeat Mom's Heart 11 timesPokey Mans	Charged KeyComplete challenge #33
34. Ultra Hard	Isaac Starts with: Key Piece 1Combined with Key Piece 2, unlocks the golden gate in the starting room of The Chest and Dark Room to fight Mega Satan. Key Piece 2Combined with Key Piece 1, unlocks the golden gate in the starting room of The Chest and Dark Room to fight Mega Satan. Curse of the Labyrinth Curse of the Blind Curse of the Lost Curse of the Maze : yes : yes All enemies spawn as champions if possible. Boss fights will be double trouble if possible. No heart pickups drop.		Defeat ??? or The Lamb for the first timeUltra Hard	Samson Feels Healthy!Complete challenge #34
35. Pong	Isaac Starts with: Cupid's ArrowGrants Isaac piercing tears that travel through enemies (but not obstacles) instead of breaking on impact with them. Rubber CementTears bounce off walls, enemies, and environmental objects. : no : yes Damage fixed at 100, tear delay fixed at 150.		Defeat Isaac 5 timesPONG	Greed's GulletComplete challenge #35