This page refers to the final boss of the game, Terror Mind. For the enemy, Lil' Terror, watch this space - the page will be created soon.

"I am simply the reaper to clean out the expired."

Terror Mind is the true main antagonist of Isaac's Adventure. It rests in Twisted Psyche until it is revived by the Haunt and The Lost in a ritual, at which point it serves as the final boss of the game.

Appearence Edit

Initially, Terror Mind appears as a segmented worm-like creature, appearing a desaturated red in colour with a circular head with four pincer-like extensions coming out from the sides, each with a sharp-pointed, bright yellow tip. From the back of its head extends a long segmented tail with a grey tip. The tip of its tail splits into two sharp ends like a two-pronged fork of some kind. On the front of its head exists a large hole with a grey rim around the outside, from which two bright red eyes can be seen. These eyes have bright yellow triangle shapes drawn inside them, rotated in order to create an expression of anger or fury.

Terror Mind's second form has that same body, but the tail has been shortened and a large black blob has emerged from the hole where its eyes were in its first form. This blob has two large red arms, each with a similarly sized black hand with red-coloured claws. On the top of its head are two long grey horns that extend to the side and a bright red flare at the top. This blob also sports a singular red eye with a white pupil.

Personality Edit

Not much is known about Terror Mind's personality, but it can be thought to be cruel and uncaring, carrying out its plans after its revival with little to no regard for what others think. It is implied it does not necessarily see its actions as evil, as it states to Isaac that by destroying Twisted Psyche it is simply doing its duty. Terror Mind appears to express pride and confidence in its abilities, as it is shocked by its defeat at the hands of Isaac. It is also quick to rage, as shown when it relentlessly attacks Isaac after finding out he still refuses to accept his fate.

In-game Encounters Edit

Twisted Psyche Edit

Terror Mind is mentioned frequently from Depths I onwards, but it only properly appears in Twisted Psyche. Upon collecting three Terror Keys from the Lil' Terrors hidden around the map, Isaac is able to enter the final gate, where the Haunt, The Lost and ??? will be performing a ritual. This is a ritual to revive Terror Mind, which is completed after the final battle with the Haunt. Once Terror Mind is successfully revived, the Haunt tries to assume control over it, commanding it to destroy Isaac. However, Terror Mind thinks nothing of the Haunt's orders and silences him, explaining that it had slightly different plans for Isaac's fate. Seeing the result of what he's done, ??? decides to return to his original stand with Isaac, giving him advice on a "rush" he gets (presumably adrenaline) that can help him emerge victorious in battle, at which point the battle begins.

In battle, Terror Mind's 1st form has 2500 HP, 90 DMG, 70 DEF and 70 SPD. It can attack using normal attacks, Blood Shot, Brimstone, The Inner Eye and Psychic Surge. It also has two skills of its own - Tail Whip and Hibernate. Terror Mind drops 400 EXP in this phase upon defeat.

Afterwards, Terror Mind expresses suprise at Isaac's strength, but assures him that he still cannot win. It then transports Isaac to a strange map named after itself, which consists of a singular floating platform. However, when Terror Mind goes to resume its operations, Isaac steps forth in defiance, choosing to resist against it and battle it once more. This enrages Terror Mind, prompting the revelation of its true form for the second phase of the fight.

During phase 2, Terror Mind has 2600 HP, 300 DMG, 800 DEF and 1 SPD. It attacks using largely the same skill set as before, but it can no longer use Hibernate or Blood Shot - these skills have been replaced with a new Terror Mind-exclusive skill, Head Smash. However, Terror Mind is also set to resist the state of Death, meaning it cannot be defeated even when its HP is 0 or below. Defeat is inevitable in this phase, and upon losing the player is sent back to the current cutscene.

Having beaten Isaac, Terror Mind scoffs at its opponent, denoting its victory as "poetic justice" before attempting to complete its task. However, it is stopped in its tracks by The Lost, who upon the realisation of the mistake she made strikes Terror Mind and joins Isaacs side for the final battle. This restores all HP for the party and increases their DMG, while Terror Mind has been weakened to the point where it can now be beaten by the player.

In the final phase, Terror Mind has 2600 HP, 130 DMG, 80 DEF and 1 SPD. To compensate for its lowered stats, Terror Mind attacks with the same skill set as in phase 2, with the addition of two new exclusive skills - Punch and Meditate. It no longer resists Death, meaning the player is now able to win the fight and receive the reward of 6000 EXP dropped by Terror Mind upon defeat.

After its final defeat, Terror Mind appears to be in a dying state. It curses its final defeat and threatens to return, stating that it will be revived again some other time before it explodes, letting out a loud screech and restoring the platform to a mound of rock on a body of water, on which the game's final cutscene plays and the game ends.

In the credits, Scatterbrain tells of a possible sequel. It is unknown whether it will see the return of Terror Mind, but it could be quite likely given Terror Mind's last lines of dialogue.



  • Terror Mind is the only boss in Isaac's Adventure who does not appear in The Binding of Isaac: Rebirth.
  • It is implied that Terror Mind is a construct of Isaac's subconcious, as the Twisted Psyche it seeks to destroy is referred to as being Isaac's.
    • This suggests Terror Mind could represent a feeling of fear that could consume people from within, which would make sense given the constant theme of fear present in the game.
  • Terror Mind is reincarnated in a ritual, implying that it died before the events of Isaac's Adventure. However, it is unknown what caused Terror Mind's death in the first place.
  • Terror Mind is one of three bosses with multiple forms. The other two are Monstro and the Haunt.
  • Oddly, in the overworld Terror Mind appears as a black ghoul-like creature with red eyes - one of the default assets in RPG Maker VX Ace. This was most likely done to save time during the game's development.
  • Terror Mind appears in the game's thumbnail as well as the title screen.
    • Oddly, Isaac's eyes in the thumbnail are changed from how they usually appear, in this instance appearing as some round transparent casing, showing the eyes of Terror Mind's 1st form underneath.
    • The thumbnail is the only place where Terror Mind's 2nd form is shown outside the main game. Everything else, including the title screen and 'Cast' screens at the end of the game, depict its 1st form only.
    • The wingding text on the thumbnail translates to "Terror shall arise" - presumably a reference to Terror Mind.
  • Terror Mind shares some of its traits with the Dark Matter species from the Kirby series of games, namely its singular red eye which appears both on its 2nd form and in Terror Haunt's mouth.
    • The troop Terror Haunt is fought in is named, 'Is it a Dark Matter?" further hinting at some kind of connection.
  • Terror Mind has numerous enemies based on it, those being Lil' Terrors and the Terror Haunt boss.
    • Terror Mind is one of two bosses to have one or more enemies based on it. The other is the Haunt.
  • Oddly, despite being a ghost Terror Mind's 1st form bears a mechanical style of appearence, with the rim around its 'face' and its eyes shaped like a type of screwhead.