A Singularity Grenade's detonation causes a gravitational singularity that pulls enemies in close and then explodes. It is a very effective way to deal damage in an open area where the enemies are scattered about and never group up close enough for grenades to be effective.
The player is immune to the initial implosion. However, the final explosion can deal self damage as normal.
Although the implosion has a large radius, far-off enemies and larger enemies will not be pulled as strongly. However, even if the grenade's final explosion does not affect all enemies, its ability to briefly stagger them can be useful when in a tight situation.