When thrown the Cluster Grenade operates like a normal grenade until it explodes. On detonation this grenade does up to 400 damage with a small radius, and then breaks into 5 smaller pieces which also explode. It is essentially a short-range MIRV Launcher, and the submunitions operate identically to its heavy cousin, down to the maximum damage (450).
Using this grenade you can have your own MIRV Launcher as the Raider. This gives a massively increased damage against stationary targets such as generators, light turrets and base turrets. It also gives you a lot of room-clearing power and if well used, a good trap. The damage done by this is enough to kill any enemy (except an upgraded Brute), a whopping 2525 if all the shells hit the same target at a close-to point blank range, which rarely happens.