From The TimeSplitters Wiki

Casualty
Game	TS2
League	Amateur League
Section	Beginners' Series
Mode	Deathmatch
Map	Hospital
Character	Dr. Peabody
Enemies Encountered	Feeder Zombie Crypt Zombie x2 Sewer Zombie Private Poorly
Rewards	Silver: Dr. Peabody Gold: Crypt Zombie
Medal Requirements	Bronze: 15 Kills Silver: 15 Kills in 5 min 30 secs Gold: 15 Kills in 3 min 30 secs Platinum: 15 kills in 1 min

The second Match of the Beginners' Series, this one isn't too different from the previous match Adios Amigos as it's quite easy to acquire a Gold Medal. Except that you now have to score 15 kills with 30 extra second than the previous match.

Briefing

Dr. Peabody left the morgue door open and now Zombies are running loose all over the Hospital. Visiting time starts in ten minutes - try to kill 15 of the living dead before then!

Strategy

The strategy for this Match isn't very different from Adios Amigos, just run around and kill things, this time zombies. The best weapons to use here are the Plasma Autorifle, ElectroTool and Homing Launcher. Just go around and kill as fast as you can, 15 kills doesn't take long to acquire here. One of the toughest things about using regular weapons here (Like Pistols) is because your fighting zombies, their heads fall off so you'll have to learn to shoot them in the middle.