From The TimeSplitters Wiki

Scrap Metal
Game	TS2
League	Amateur League
Section	Mode Madness
Mode	Vampire
Map	Scrapyard
Character	Female Trooper
Enemies Encountered	ChassisBot
Rewards	Bronze: Scrapyard Gold: ChassisBot
Medal Requirements	Bronze: 10 Kills Silver: 10 Kills in 4 mins Gold: 10 Kills in 3 mins

Scrap Metal introduces you to Vampire, you die if you don't kill before the bar depletes.

Briefing

UltraNet headquarters want this ChassisBot disposed of as quickly as possible. Although not heavily armored, it is very agile, so be careful! Power drained from the ChassisBot will refresh you EnviroSuit batteries - don't let them run down!

Strategy

Be careful, this is Vampire, which means that you will die in a certain amount of time. When the bar at the top of the screen depletes, you die, so quick kills is a must. Pick up a weapon that kills fast, like the Homing Launcher or the Plasma Autorifle. Don't wait for the ChassisBot to find you, use the radar and find it. Also, not every kill will refill your life bar back to full, sometimes a kill will only refill the bar to about half or so. Find a powerful weapon and stay on top of the situation. For maximum kills, stick to the big, open-roofed area, this is where the most respawn points are.