Invincibility

Invincibility is a new piece of equipment featured in Halo 3.

It confers the user with a brief period of invulnerability. This period lasts about 10 seconds. When activated the player is covered in shining bands. It is known to be possessed by some or all Brute Chieftains in Halo 3, giving chieftains a brief period of time where they may chase after the player with the Gravity Hammer unhindered, giving them a significant tactical advantage. In campaign, it can be found on some dead Brute Chieftains that haven't used a power-up yet. Curiously, if you melee a Brute in the back (assassination hit) while the invincibility is active, it will still kill him. In addition to being obtainable from dead Brute Chieftains, there is an Invincibility in the level "Halo". At the top of the Control Room tower, where you have to fight hordes of Flood, there is an Invincibility. After going up the staircase, go to the left and into the tunnel. It will be there. Note: This is only found on difficulties Easy, Normal and Heroic. It cannot be found there on Legendary.

It has a similar appearance to the Cloaking equipment, except that it glows a gold color, rather than a cool blue color. It's symbol on the HUD is Two overlapping, intersecting ovals.

It is not present in multiplayer, unless you edit gameplay options where you can make players invincible. NOTE: The guardians can still kill you.

In campaign, though you will be invulnerable from almost all forms of attack, you may still die from falling or having a large object such as a Scorpion crush you, or by having tons of Infection forms infect you. Immortal characters like the Arbiter who become betrayed by you can also kill you.

Trivia

 * A player is able to take a Brute Chieftain's Invincibility if they assassinate, head shot, or in some way kill the Chieftain before it can activate it.
 * The only way to kill an invincible Chieftain or player is to assassinate them, or to wait for the Invincibilty to wear off.

Disadvantages

 * If you are trying to kill the Brute Chieftain who is using invincibility grenades will just bounce off him unless you stick his weapon.
 * Players or Brutes who are invincible can still be killed by being assassinated, crushed or falling from a large height.