Dice Rooms and Special Rooms#
Every floor’s map in The Binding of Isaac spawns a variety of special rooms at random. This page focuses on the most distinctive of them - the Dice Room - and fully maps out the standalone family of dice active items (D1, D4, The D6, Eternal D6, D7, D8, D10, D12, D20, D100, D∞, Spindown Dice), then closes with the mechanics and strategies of other special rooms: the Library, Arcade, Sacrifice Room and Crawlspace. Content on this page follows the Repentance expansion
The Dice Room#
A giant die sits at the center of a Dice Room; stepping on it instantly triggers a reroll (Reroll) effect matching the face rolled. The Dice Room is the game’s quintessential “comeback room” - it can wash the whole floor’s item layout, or even your entire build, clean. Key restriction: the die triggers only once - once stepped on, this room’s die is spent.
The six face effects#
| Face | Triggered effect | Value rating |
|---|---|---|
| 1 | Same effect as D4 - rerolls all of Isaac’s items (using the original room’s item pool) | ⭐⭐⭐⭐⭐ |
| 2 | Same effect as D20 - rerolls all pickups (Pickup) in the room | ⭐⭐ |
| 3 | Rerolls all pickups and trinkets (Trinket) on the floor - shop pickups have a chance to reroll into items; excludes Black Markets, Crawlspaces, Devil Rooms and Angel Rooms | ⭐⭐⭐⭐ |
| 4 | Same effect as D6 - rerolls all pedestal items (Pedestal Item) on the floor - likewise excluding Black Markets, Crawlspaces, Devil Rooms and Angel Rooms | ⭐⭐⭐⭐⭐ |
| 5 | Same effect as “Forget Me Now” - the entire floor regenerates and you return to the floor’s start | ⭐⭐⭐ |
| 6 | Same effect as D100 - triggers all effects of 1 + 3 + 4 at once (reroll your items + all floor pickups and trinkets + all floor pedestal items) | ⭐⭐⭐⭐⭐ |
Face-by-face strategy#
| Face | Strategy advice |
|---|---|
| 1 | The number one shuffling tool when your build is weak - if all your items are duds, gamble on a new set in a face-1 room. Note the reroll uses the original room’s pool and is fully random - your existing core items get washed too |
| 2 | Rerolls the room’s pickups - step on it in passing - not worth a special detour |
| 3 | Best stepped on after clearing the floor - all floor pickups and trinkets get replaced at once, and shop pickups may upgrade into items; Black Market, Crawlspace, Devil Room and Angel Room contents are unaffected - do not expect it to reroll Devil deals |
| 4 | Rerolls all floor pedestal items - everything unclaimed in Treasure Rooms and shops re-rolls into a new pool. Take pedestal items you want to keep before stepping on the die |
| 5 | Regenerates the whole floor and returns you to its start - for when you dislike the floor’s layout and want to replan your route. Regenerated room contents defer to the game - confirm nothing key was left behind before triggering |
| 6 | The ultimate shuffle, three rerolls in one trigger - the weaker your build, the more it is worth stepping on - once your build is online, steer clear so your core synergies are not washed away |
Usage notes#
- A Dice Room’s die is one-use - spent once stepped on - there is no farming the same die repeatedly
- Faces 1 and 4 match D4 and D6 respectively - but the Dice Room’s reroll scale dwarfs the item versions: one is “all your items”, the other “all floor pedestal items” - use dice items for precise single-room rerolls, Dice Rooms for a big wash
- Faces 3 and 4 both do not act on items inside Black Markets (Black Market), Crawlspaces, Devil Rooms or Angel Rooms
- Face 6 triggers 1 + 3 + 4 at once - the fiercest and most thorough face in the Dice Room - weigh your current build before stepping on
- Dice Rooms are rare special rooms - a high-value target whenever one appears - if the map shows the marker, route toward it first
Dice active items (Dice Items)#
A Dice Room is “step on it, reroll for free”; dice active items put reroll power in your hands - equip one and spend charges (Charge) to use it anytime. The two systems share effects but are fully independent: a Dice Room is once per floor, dice items can be used repeatedly as long as they charge.
Full dice active item table#
| Item | Charges | Effect |
|---|---|---|
| D1 | 4 | Duplicates 1 random pickup, trinket or chest |
| D4 | 6 | Rerolls all of Isaac’s items |
| The D6 | 6 | Rerolls all pedestal items in the room - the starting item of “???” |
| Eternal D6 | 2 | Rerolls the room’s items - but each item has a 25% chance to vanish outright |
| D7 | 3 | Restarts the room, respawning its monsters |
| D8 | 4 | Rerolls stats - tears, damage, range, speed |
| D10 | 2 | Replaces the room’s enemies with weaker versions |
| D12 | 3 | Rerolls obstacles - rocks and the like are all replaced |
| D20 | 6 | Rerolls all pickups, chests and trinkets on the floor |
| D100 | 6 | Triggers every dice effect in sequence - except Eternal D6 and Spindown Dice |
| D∞ | 2 | Switch between the dice effects above - use whichever you want |
| Spindown Dice | 6 | Steps a room’s pedestal item down one internal ID, rerolling “one number at a time” - unlocked by defeating Delirium as Tainted Isaac |
Notes on key items#
| Item | How to use it |
|---|---|
| The D6 | The lowest-friction dice item - reroll whenever a room’s pedestal item disappoints - the 6-charge cycle supports high-frequency use. “???” starts with it, making it the entry point of this system |
| D4 | The ability to scrap and rebuild your whole set - the comeback card of a weak build - but it can also scatter a finished strong synergy - a high-gamble item |
| Eternal D6 | Very low charge, reroll often - at the cost of a 25% chance per item to vanish outright - fits when you have plenty of items and can afford the attrition |
| D7 | Restarts the room and respawns monsters - use it when a room’s monster mix is particularly nasty - a great helper in clear-the-room challenges |
| D8 | Rerolls tears, damage, range and speed - gamble when your starting stats are deformed - defer to the actual in-game panel |
| D10 | A pre-fight rescue tool - swap out enemies when a room’s difficulty is absurd |
| D12 | Rerolls obstacles - use when a rock maze blocks the path, you need cover, or need to blast an opening |
| D20 | Replaces all floor pickups, chests and trinkets at once - biggest payoff when used after clearing the floor |
| D100 | Triggers every dice effect in sequence - one use equals a full reroll suite - note it excludes the effects of Eternal D6 and Spindown Dice |
| D∞ | Switchable effects - decide what you currently lack first (pedestal items: D6-type; resources: D20-type; stats: D8-type) then lock it in - far more forgiving than any single die |
| Spindown Dice | Steps pedestal items down one internal ID at a time - a targeted “swap” approach - chain uses walk an item down the item list step by step - very strong when hunting a specific item. Unlocked by defeating Delirium as Tainted Isaac |
Dice Shard and Cracked Dice#
Beyond active items, the dice family has two “off-brand” members:
| Name | Type | Effect |
|---|---|---|
| Dice Shard | One-use consumable | Triggers a random dice effect when used |
| Cracked Dice | Trinket | Has a chance to trigger a random dice effect when hit |
Both effects are random - you cannot pick a specific die - luck-based supplements at best; do not build around them.
The Library#
A Library is a special room built around bookshelves, holding several book-type active items. Book items often carry unique active effects - a major source for active-item builds.
- Before entering a Library, check your active item slot - is the current book worth replacing - never drop a core active just to grab a book
- Multiple book items share transformation (Transformation) synergies - collecting enough triggers the book-worm style transformation - exact combos defer to the in-game collection
- With The D6 in hand - pedestal items in a Library can be rerolled directly - swap any book that does not fit
The Arcade#
Arcades are lined with coin-operated machines - blood donation machines, fortune machines, donation machines and more - and may spawn a Beggar. The Arcade is a classic resource room: coins and health go in - random rewards come out.
| Machine | How it plays | Strategy |
|---|---|---|
| Blood donation machine | Pays out random rewards at the cost of red hearts | Only touch it with health to spare or a way to heal back - otherwise it is self-harm |
| Fortune machine | Insert coins for random rewards | Play in passing when coins are plentiful - pure luck |
| Donation machine | Deposit coins - accumulate progress for save-wide rewards | A long-term investment - worth depositing whenever you pass one each floor |
| Beggar | Give coins for random rewards | Small inputs suffice - returns are fully random |
Exact costs and payouts of each machine defer to the game. Donation machine progress persists across runs - long-term deposits gradually unlock shop-related content - the single long-term investment most worth keeping up in the entire save file.
The Sacrifice Room#
A spike altar sits at the center of a Sacrifice Room - stepping on it costs health and sacrifices once to the altar for a random reward. The more consecutive sacrifices, the higher the reward tier - high sacrifice counts tie directly into Angel Room (Angel Room) rewards - exact counts and rewards defer to the game.
Strategy points:
- Enter only with health to spare - every sacrifice costs real health - the price climbs with each one
- Bringing healing (lifesteal items, healing consumables) amplifies the Sacrifice Room’s value - sacrifice continuously for Angel-side rewards
- For an Angel Room route - the Sacrifice Room is the most proactive way in - far more controllable than waiting for an Angel Room door to spawn
The Crawlspace#
A Crawlspace is a secret compartment hidden “under the floor” - bomb a crack to open the hole and drop in. Inside you usually find pickups, chests or items - scale and quality are random.
- With bombs to spare - bomb suspicious wall seams a few extra times - a Crawlspace entrance looks different from an ordinary crack
- Some items and trinkets help locate Crawlspaces - the exact list defers to the game
- Full-clear playstyles treat Crawlspaces as a “bonus reward floor” - a few spare bombs per floor always pay off
Other special rooms at a glance#
| Room | Mechanic | Strategy |
|---|---|---|
| Treasure Room | Offers one free pedestal item | A must-visit every floor - think about your build before taking |
| Shop | Buy items and supplies with coins | The resource hub of economy builds |
| Boss Room | The exit to the next floor appears after defeating the Boss | Mandatory for clearing - Boss reward items are the main between-floor growth |
| Curse Room | Entry and exit cost health via spikes - inside are devil-side rewards | A high-value trade when your health is healthy |
| Challenge Room | Clear a wave of enemies for a reward | Enter only when your combat power suffices |
| Boss Challenge Room | Chain several Bosses for high-quality rewards | High reward but high risk - judge your strength |
| Super Secret Room | An extremely hidden compartment - connected to only one room | Worth finding with bombs to spare - contents are usually not bad |
| Black Market | A devil-deal zone hidden inside a Crawlspace | An extension of the Devil Room system - talk trades only when healthy |
Special rooms are assigned at random when each floor’s map generates - some special rooms require a minimum number of normal rooms on the floor - the more rooms, the likelier they appear - exact spawn weights defer to the game. Prioritize routing toward high-value rooms like Dice Rooms, Sacrifice Rooms and Black Markets whenever they show up.
FAQ#
| Question | Answer |
|---|---|
| Can a Dice Room die be reused? | No - it is spent after one trigger - each Dice Room holds exactly one chance |
| Are Dice Rooms and dice items the same thing? | No - a Dice Room is a map special room: step on the central die to trigger a fixed face effect, once per floor; dice items are active items that spend charges for repeated use. Their effects share origins - Dice Room face 1 = D4, face 4 = D6, face 6 = D100 - but trigger method and scope differ completely |
| Is a face-6 Dice Room worth stepping on? | It triggers all effects of 1 + 3 + 4 at once - the most thorough shuffle a Dice Room offers. Worth the gamble when your build is weak - steer clear once your build is online |
| Can shop items be dice-rerolled? | Dice Room face 3 rerolls all floor pickups and trinkets - shop pickups may reroll into items - but faces 3 and 4 never act on the inside of Devil Rooms, Angel Rooms, Black Markets or Crawlspaces |
| How is Spindown Dice unlocked? | Defeat Delirium as Tainted Isaac |
| Can dice items choose their effect? | Each dice item’s effect is fixed - only D∞ can switch between dice effects - Dice Shards and Cracked Dice trigger random effects |