Power drain

The power drain is a combat support device designed and developed by the Covenant for its infantry forces. The equipment has several colloquial nicknames among United Nations Space Command personnel, including "Draino" and "Drainer".

Design details
The power drain is a roughly spherical device massing 11.2 lb. When activated, the device emits a blue electromagnetic pulse field for around 6.5 seconds, after which the device self-destructs in a small explosion. The EMP is used to short out the electrical systems of any equipment caught within range, including energy shielding and light vehicles. During its activation, two cylindrical emitters are extruded from the sides of the sphere.

The power drain has a visual resemblance to the flare and radar jammer equipment also developed by the Covenant, save for its blue colouration. The Flare, developed by the Jiralhanae, was based on the same technology as the power drain and radar jammer.

Usage
The power drain is a piece of infantry support equipment developed by the Covenant, and was heavily employed by the Jiralhanae loyalist forces of the Prophet of Truth during the final weeks of the Human-Covenant War. Despite their origin, human forces were more than willing to make use of captured enemy power drains during the war.

Halo 3 and Halo 3: ODST
The power drain is one of several pieces of deployable equipment featured in Halo 3. When thrown, the power drain takes 0.5 seconds to activate, and subsequently lasts 6.5 seconds, equaling a total of 7 seconds. The effects of the power drain pass through walls and floors, so simply fleeing to the bottom floor of a structure after an enemy activates one will still strip one's shields if one passes through the field. This is most noticeable on maps like Guardian.

The power drain can be used in a glitch called Equipment jumping by moving against a wall, jumping, and then at highest point of the jump deploying the power drain. This allows a player to jump off of it in mid-air. This is a great tactic for reaching high areas of a map, such as the second level of the tower on The Pit. This can also be done with the radar jammer and flare. The power drain variation of the glitch is commonly claimed to only be able to be performed as an Elite. This is not the case, but it is exceedingly difficult to do as a Spartan in the Xbox 360 version of Halo 3; thus, only a few instances of it have been documented. It appears to be easier to accomplish while playing as a Spartan in the Halo 3 portion of Halo: The Master Chief Collection.

In Halo 3: ODST, the power drain performs as it did in Halo 3 though cannot be used by the player. It is only used by Brute enemies; when the player is in the radius of a power drain, their health will drain in addition to their shields.

List of appearances

 * Halo 3
 * Halo 3: ODST