This is best completed against a large group of smaller enemies, such as in the arena segments of some levels. You simply need to find a bunch of eight or more enemies gathered near each other. If the enemies are within the blast radius of the Plasmabomb Launcher, then they will die.
If using a human team-mate, this trophy can be easier as the team-mate can lure enemies to them, so that they are all gathered up in a certain location, making aiming easier.
- Ratchet & Clank: All 4 One (first appearance)