User:Blcd/RandomTidbits

From Binding of Isaac: Rebirth Wiki
Jump to: navigation, search

What?[edit | edit source]

This page contains random information gathered by reverse engineering that has yet to make it into a relevant page. Feel free to use this information and enhance relevant pages. Also feel free to message me on discord or edit my talk page with any research requests.

Items[edit | edit source]

Head of the Keeper[edit | edit source]

5% chance for a coin to spawn when hitting a vulnerable enemy.

Void[edit | edit source]

Active items are activated in the order they were consumed. When consuming multiple items at once, they are added based on where they appear in the room's entity list. For example

 for entity in roomEntities do
   if (isPedistal(entity) and isActiveItem(entity)) then
     consume(entity) #Add to consumedItems list
   end
 end 
 for item in consumedItems do
   UseActiveItem(item)
   if isSingleUse(item) then
     remove(item)
   end
 end

Athame/Maw[edit | edit source]

  • Athame is a 15% chance on kill to spawn a blackheart. Maw is a 5% chance on kill to spawn a blackheart. If both proc, the black heart drop percentage is whatever one triggered last.
  • The effect can stack (E.g. Athame + Razor Blade). This can cause multiple hearts to spawn if the killing damage from multiple effects all trigger on the same frame. Here is an example showing this behavior with a 100% drop rate. https://www.youtube.com/watch?v=ppXu5A2FvS8.

Dead Eye[edit | edit source]

Upon missing there is an increasing chance to lose the buff.

  • first miss = 20%
  • second miss = 33%
  • third miss and beyond = 50%

Delirious[edit | edit source]

Delirious can spawn the following bosses(v193) http://pastebin.com/simKrthQ

Monster Manual[edit | edit source]

The list of familiars Monster Manual picks from.

Name
Brother Bobby
Cube of Meat
Halo of Flies
Distant Admiration
Sister Maggy
Little Chubby
Robo-Baby
Little Gish
Little Steven
Guardian Angel
Demon Baby
Forever Alone
Smart Fly
Dry Baby
Juicy Sack
Robo-Baby 2.0
Rotten Baby
Headless Baby
Leech
Bob's Brain
Lil Brimstone
Lil Haunt
Big Fan
Sissy Longlegs
Gemini
???'s Only Friend
Ball of Bandages

D4[edit | edit source]

D4 rerolling excludes the following items.

Id Name
10 Halo of Flies
81 Dead Cat
238 Key Piece 1
239 Key Piece 2
258 Missing No.
327 The Polaroid
328 The Negative
376 Restock (only in greed mode)
474 Tonsil

Familiars[edit | edit source]

Lil' Chest[edit | edit source]

Upon clearing a room, Lil' Chest has a random chance to spawn a consumable or trinket. The drop chance is seeded, however the drop itself is not seeded.

  • Chances without BFFs!
    • 10% for a trinket
    • 25% for a consumable
  • Chances with BFFs!
    • 12.5% for a trinket
    • 31.25% for a consumable

Bomb Bag[edit | edit source]

The bomb bag drops a bomb after a certain number of room clears. Note the room clears is tracked per familiar.

  • Without BFFs!
    • floor(roomsCleared / 1.1) > 0 && (floor(roomsCleared / 1.1) & 1) == 0
  • With BFFs!
    • floor(roomsCleared / 1.2) > 0 && (floor(roomsCleared / 1.2) & 1) == 0

Pickup Familiars[edit | edit source]

ID Name Normal BFFS! Notes
94 Sack of Pennies cleared > 0 && cleared & 1 == 0

cleared > 0 && (cleared & 1 == 0 || rand() % 3 == 0)

96 Little C.H.A.D. floor(cleared / 1.1) > 0 && floor(cleared / 1.1) & 1 == 0 floor(cleared / 1.2) > 0 && floor(cleared / 1.2) & 1 == 0
98 The Relic floor(cleared / 1.11) & 3 == 2 floor(cleared / 1.15) & 3 == 2
131 Bomb Bag floor(cleared / 1.1) > 0 && floor(cleared / 1.1) & 1 == 0 floor(cleared / 1.2) > 0 && floor(cleared / 1.2) & 1 == 0
266 Juicy Sack 1-2 blue spiders (seeded) +1 blue spider
271 Mystery Sack floor(cleared / 1.11) & 3 == 2 floor(cleared / 1.15) & 3 == 2 Drops Hearts, Coins, Keys and Bombs. The drop's type is seeded but the subType is unseeded. The drop function explicitly passes a subtype instead of 0. The ranges are, Hearts = 1-6, Coins = 1-4, Keys = 1-3, Bombs = 1-2.
362 Lil' Chest See the section above
385 Bumbo 32% 40% Level 2 Bumbo has a chance to drop a pickup on room clear.
389 Rune Bag floor(cleared / 1.11) & 3 == 2 floor(cleared / 1.15) & 3 == 2
403 Spider Mod 10% 12.5%(1 in 8) If the roll succeeds, 2/3 chance to spawn a blue spider, 1/3 chance to spawn a battery.
491 Acid Baby floor(cleared / 1.1) > 0 && floor(cleared / 1.1) & 1 == 0 floor(cleared / 1.2) > 0 && floor(cleared / 1.2) & 1 == 0
500 Sack of Sacks floor(cleared / 1.1) > 0 && floor(cleared / 1.1) & 1 == 0 floor(cleared / 1.2) > 0 && floor(cleared / 1.2) & 1 == 0

Monsters[edit | edit source]

Host[edit | edit source]

Every 2 damage(rounded up) will add 7 frames of hiding up to a max of 70. Hosts take 14 frames to acquire a target. Dealing 20+ damage will cause the host to grimace.

Machine destruction drops[edit | edit source]

These are the drops when you destroy a machine(excluding restock, blood donation and the chest/darkroom).

  • 20% (pill or trinket)
  • 1% chest
  • 1% locked chest
  • 78%
    • 33% for one of these conditions to happen based on trinkets you are holding. They are checked in this order in the case of having multiple matching trinkets. Ace of Spades = 50% spawn a card || Safety Cap = 50% spawn a pill || Match Stick = 50% spawn a bomb || Child's Heart = 50% spawn a heart || Rusted Key = 50% spawn a key
    • 100% Drop 2-3 pickups (33% +1 pickup if you have lucky toe)
      • 35% spawn 1-3 coins
      • 20% spawn a heart (50% this counts as 2 pickups, 80% chance daemon's tail prevents this to spawn, if prevented this doesn't count towards the pickup drops)
      • 15% spawn a key
      • 30% spawn a bomb

Room Anti-softlock[edit | edit source]

This is the feature where doors will open after a set time. The anti-softlock check fires every 2 seconds after being in a room for 30 seconds. These are the door open conditions

  • Only works in RoomType.ROOM_DEFAULT
  • Doesn't trigger if there is a boss/miniboss in the room or the player has flying
  • The remaining enemies must be unable to path to the player (Ignoring poop)
  • The remaining enemies must have GridCollisionClass COLLISION_WALL or COLLISION_WALL_EXCEPT_PLAYER