Custom Powerup

The Custom Powerup is an object in Halo 3, similar to the Active Camouflage and the Overshield in the way that it seems held together by small magnets.

Overview
This object can only be placed on maps by using Forge. What it does is determined by a player when setting up a custom gametype. But by default, it increases the player's speed. It can affect many player attributes, such as damage resistance, gravity, damage, etc., including multiple simultaneous effects. It can make a player an "instant Juggernaut", or even negatively affect a player. It will appear as a floating yellow orb, and its effects can be edited by tapping 'X' at the custom games lobby to go to game options menu, and then to the bottom of the 'weapons and vehicles' tab. MLG have their own custom powerup which provides 3X Overshields in their official MLG playlist.

Trivia

 * The default settings for the custom powerup (which is speed increase) are from a never implemented Agility Powerup.
 * On default your melee attacks are multiplied three fold and your speed is increased by 50%.