- Delirium will teleport around the room, sending out an array of white projectiles and green projectiles that explode like Ipecac.
- Its most notable (and dangerous) attack is that it will transform into bosses previously encountered during the run, including a few of the "final" bosses (Mom, It Lives, etc.).
- While transformed, it will attack with its white projectiles along with the attacks of the boss it is transformed into, though it cannot attack with its explosive projectiles.
- When it transforms into a boss, Delirium retains its own health, not the health of the boss it transformed into.
- The attacks of the transformed boss are dependent on Delirium's current HP. For example, if Delirium transforms into War while at <50% HP, it will be horseless and run at Isaac.
- It can rarely transform into two instances of the same boss.
- Whether it turns into champion variants or regular variants is random and does not depend on which variant was previously defeated. For instance, it can turn into black Gurdy, even if the regular Gurdy was the defeated variant, and vice-versa.
- It is unable to properly transform into Hush.
- Progressively, it will alternate through each form faster and become more aggressive.
Upon defeat, the screen will start to glitch and fill with static while short moments from the current run are played. After being defeated, Delirium will burst into blood and drop a Final Boss Chest, playing the Final Ending.
- Delirium is immune to Chaos Card.
- Plan C is ineffective against Delirium. Because his death animation is longer than 3 seconds, Isaac will still be killed first.
- Most entities that are considered to be bosses by the game (usually identified by ones that add the boss health bar to the screen) are marked as bosses that Delirium can transform into.
- The Seven Sins are exceptions to this.
- Delirium can transform into either form of Satan.
- When transformed into the Gurglings or the Turdlings, it will only appear as one instead of two.
- When transformed into The Headless Horseman, it transforms into either the head or the body, but it doesn't transform into both.
- Each size of Fistula and Teratoma count as their own separate boss which Delirium can transform into just like any other boss.
- This also results in many bugs due to unaccounted for transformations. These can be viewed in the Bugs section of this page.
- When transformed into a boss that has multiple segments, the extra segments can be killed. The head, however, cannot.
- This also applies to Gemini - Suture can be killed but Contusion cannot.
- All parts of Fistula and Teratoma can be killed (though they have much greater health than normal), and the room will remain empty until Delirium transforms again. Even though the segments have been killed, Delirium itself has not been killed.
- When transformed into two instances of the same boss (like Lokii or Sisters Vis), one of them can be killed but the other cannot.
- Unlike the real Mom, Delirium's Mom form will only stomp and will not spawn enemies.
- If Delirium transforms into Gemini then undergoes another transformation, Suture doesn't disappear. Instead, he will come after the player like the normal version does after Contusion is killed.
- If Delirium transforms into The Lamb's second phase then undergoes another transformation, the body doesn't disappear and can be killed, just like the real Lamb's body.
Delirium as Gurglings.
Delirium as Little Horn.
Delirium as Turdlings.
Delirium as Rag Man.
Delirium as Famine.
Delirium as Gemini.
Delirium as Steven.
Delirium as Blighted Ovum.
Delirium as The Duke of Flies.
Delirium as The Husk.
Delirium as Larry Jr..
Delirium as The Hollow.
Delirium as The Haunt.
Delirium as The Forsaken
Delirium as Widow.
Delirium as The Wretched.
Delirium as Pin.
Delirium as The Frail.
Delirium as Monstro.
Delirium as Monstro II.
Delirium as Gish.
Delirium as Fistula.
Delirium as Teratoma.
Delirium as Gurdy Jr..
Delirium as Rag Mega.
Delirium as Gurdy.
Delirium as Big Horn.
Delirium as Pestilence.
Delirium as Polycephalus.
Delirium as The Stain.
Delirium as Chub.
Delirium as C.H.A.D..
Delirium as Carrion Queen.
Delirium as Mega Fatty.
Delirium as The Cage.
Delirium as Dark One.
Delirium as The Adversary.
Delirium as Peep.
Delirium as The Bloat.
Delirium as Mega Maw.
Delirium as The Gate.
Delirium as Brownie.
Delirium as Mask of Infamy.
Delirium as Sisters Vis.
Delirium as War.
Delirium as Loki.
Delirium as Lokii.
Delirium as Blastocyst.
Delirium as Scolex.
Delirium as Death.
Delirium as Conquest.
Delirium as Daddy Long Legs.
Delirium as Triachnid.
Delirium as Mr. Fred.
Delirium as Mama Gurdy.
Delirium as The Matriarch.
Delirium as The Fallen.
Delirium as The Headless Horseman.
Delirium as Krampus.
Delirium as Uriel.
Delirium as Gabriel.
Delirium as Mom.
Delirium as Mom's Heart.
Delirium as It Lives.
Delirium as Satan.
Delirium as Isaac.
Delirium as ???.
Delirium as The Lamb.
Delirium as Mega Satan.
Delirium as Hush. (First phase only)
Delirium's main Form on Isaac's last will.
- Delirium is the only enemy immune to Chaos Card.
- Killing Delirium in a daily run counts as winning it. However, this does not reward any unique bonus points.
- Unlike other completion marks, defeating Delirium does not add a mark to the post-it note. Instead, the note will become tattered (with blood on hard mode).
- If no other bosses have been encountered during the run, Delirium will be unable to transform.
- This is normally impossible as you have to defeat at least one boss, even if extremely lucky. Use floor skips such as Ehwaz or We Need to Go Deeper! until Chapter 3. After the fight with Mom, Isaac has a 5% chance of teleporting to The Void, but only if Isaac has 10+ tear damage or 20+ items. Then, you must find Delirium without encountering any other bosses.
- There was a glitch in the original version of The Binding of Isaac: Afterbirth † which caused Delirium's main form to lack an idle animation. This was soon patched.
- In the game files, there is an unused Delirium transformation of Ultra Greed with a beard.
- Delirium can transform into Ultra Greed if he is encountered, but this is normally impossible as the bosses never appear in the same game mode.
- Delirium is Isaac's manifestation of the "white light at the end of the tunnel" where the entire history of his life flashes before his eyes, moments before Isaac's death.
- This might be reflected by Delirium's death animation and its ability to shapeshift into different bosses you previously encounter.
- Every time Delirium transforms into another boss, it adds onto the encounters counter in the Bestiary.
|The Binding of Isaac: Rebirth|
|Achievements||Attributes||Bosses||Cards and Runes||Challenges||Chapters|