Invulnerability Glitch

Invulnerability glitch, sometimes called invul, is a glitch that allows Jak to stay alive while in a dead/dying state. The glitch is primarily used in the Any% and Gunless categories to assist with boss fights and make specific skips possible. The glitch is removed by bonking into a wall, clipping inside of an enemy's character model as it attacks, using the warp gate, dying in the void, resetting mission, loading a save file, or dying by too much fall damage.

Technical

The invulnerability glitch has two different states: State 1 and State 2. More commonly referred to as Invul 1 and Invul 2. By interrupting Jak's death sequence on the same frame it is supposed to occur, Jak can enter an invulnerability state where he is allowed to move throughout the world, but the game thinks he is dead. Actions that can interrupt the death sequence include dismounting the JET-Board and swimming up through a plane of dark eco.

Invul 1

When Jak first interrupts the death sequence, Jak is able to traverse on death planes and continue moving within the world. However, the game believes Jak is dead, which causes the following side effects:

• Enemies will no longer target Jak.
• Jak can't pick up ammunition, skull gems, eco, or precursor orbs.
• Jak can't use vehicles, weapons, Dark Jak, or the JET-Board.
• Jak can't speak to non-playable characters or side mission holographic terminals.
• Jak can't ledge grab.
• Jak can walk on all death planes except the void.

Invul 2

To achieve the second state of invulnerability, Jak needs to take fall damage. Or "splat" as some call it. The splat animation that occurs when taking fall damage acts as a check that lets the game know that Jak is still alive. After the splat, all of the side effects of Invul 1 will be negated except the main invulnerability effect.

Discovery

The JET-Board method of entering the invulnerability state was discovered by Djtomjak73 on September 11, 2015.