Power drain

The Power Drain is a short-range magnetic offensive weapon featured in Halo 3.

Function
The power drain creates a short-range magnetic induction effect which causes disastrous failure of powered field systems within a set radius, and is designed primarily to interfere with common varieties of field-based shielding, vehicle and power generation. It also has a damaging effect on biological systems and can wound or kill most bipeds in its resulting explosion. Essentially, the Power Drain is like a reverse Regenerator; instead of energizing a player's shields, it causes any player's shields within the area of effect to drain away, making them vulnerable to harm. Plus, if you stand near it in the resulting explosion, with stripped shields, you will get killed. The Power Drain can also disable vehicles, rendering them unable to move when they drive or fly through it and even about 5 seconds afterwards. If a Regenerator and Power Drain are deployed in close proximity, the Regenerator will stop working.

The Power Drain, like the Bubble Shield, Trip Mine, Radar Jammer and the Portable Gravity Lift, are all in the category of equipment and can be deployed using the "X" Button. It activates a very short time after it is thrown - it has just enough inactive time to travel away from the user, leaving them unaffected.

In the Multiplayer Beta, the players got the Power Drain and the Bubble Shield mixed up and ended up dying or shielding the enemy player.

The power drain can even disable non drivable vehicles like the Scarab as seen in TGS Demo Part 2 link. In fact it will affect any device that runs on any type of energy within its radius in game.

Spawns
High Ground

The power drain can be found on a small metal ledge inside the main compound of the High Ground base. The ledge is within jumping distance of the flag spot.

Snowbound

The power drain spawns inside "Low Base" on Snowbound.

Valhalla

The power drain spawns near the center man cannon at either side on Valhalla.

The Pit

The power drain is located in the center of the map, on the bridge connecting the upper level to the control room (between each base).

Narrows

The power drain spawns right in front of the man cannon on each side of the map.

Last Resort

The power drain is found on the small set of stairs in the back corner of the main base.

Construct

The power drain can be found in two places; the first is at the bottom of the yellow gravity lift to the top of the map, the second is next to the sword spawn on the enclosed catwalk on the top level.

Sandtrap

The power drain is found inside one of the buildings with a Man cannon in the centre of it.

Trivia

 * It shares many physical similarities with the Radar Jammer and Flare, with exception of a non-metal color.
 * It is also capable of draining vehicle power as well, causing the vehicle to stop in its tracks or malfunction. If a vehicle gets in the radius of the drainer for even a brief moment they would lose control of the vehicle. A Bungie employee remarked that "the guy" he just boarded used the Power Drain to once again disable the Banshee."
 * Although the Power Drainer disables the vehicle's movement, any armaments (etc. Scorpion Turret, Hog turret)on the vehicle will still work.
 * Sometimes throwing the Power Drain at UNSC forces can gradually drain their health over time, resulting in a kill before the explosion.