[!Skill Point Notification!]
One of thirty skill points within the game and the only one truly available to this planet (Command Center), this one will require you to use the Infector weapon on the denizens. However, there are two catches to this situation.
1) There's a limited amount of enemies and they are rather strengthened. For this reason, you will want to use the V5 (or if this is challenge mode, probably the V8) version of the weapon for added strength.
2) You have to infect AND KILL thirty enemies. I shall mark the location of nearby ammo crates with an asterisk. If I can count them from memory, we have...
2 patrolling the front door. (2)
1 waiting within the door. (3)
2 minor grunts hiding behind the openings leading back out. (5)
2 more minor grunts standing on top of towers to greet you when you exit. (7)
2 minor grunts on the magnetic wall. (9)
4 defense drones after you pass the two Tyrrha-Guise mini-games. (13)
2 minor grunts and 1 patrol on the other side of the gap. (16)
2 more minor grunts in the door behind the patrol. (18)
4 more defense drones up the walkway. (22)
From there, it can get a bit messy. You've got two large grunts up on towers, about 4 more defense drones, and I think 3 minor grunts within this room. Try to mark and kill them as best as you can. Beyond this room are three more minor grunts in a laser puzzle room, then several more targets in the unlocked walkway beyond. I got the trophy prior to the laser room. The larger grunts require about three hits with the Infecto-Bomb weapon, the smaller ones two, and if you simply infect the drones, they'll kill themselves after you use one.