Plasma grenades are very rare, but powerful thrown explosives. When detonated, a small explosive in the grenade ruptures the magnetic seal containing a charge of superheated plasma energy.
It is not recommended to use them against the Enclave soldiers as their advanced power armor can absorb around 50-80% damage. However, just about everyone and everything else has a low plasma resistance, making this grenade type the most useful late to end game.
Used by the Hubologists. In random encounters featuring five standing in a circle, one is guaranteed to have several on their person. Unlike most other situations, failing a steal does not cause them to go hostile or damage your Karma/reputation, making plasma grenades potentially more plentiful than frag grenades.
Sometimes used by mercenaries in random encounters.