MW2 (No, not what you're thinking... I mean Mechwarrior 2).
Team battle, anything from 2vs2 to 4vs4.
Step 1.) One player does the following:
Jenner IIC
Strip the Mech down.
Equip the largest engine possible and MASC.
Add as much armour as possible without putting ANY on the rear torso sections.
Add one SRM launcher. Fill the rest of the Mech with missiles for it.
Step 2.) At least one ally equips a Gauss Rifle.
Step 3.) The Jenner runs into the middle of the enemy group, and everyone shoots it in the back.
Step 4.) A Dire Wolf might survive this. If this happens, one more Gauss hit to the torso will kill it.
I NEVER saw this tactic fail, but it always felt unfair.
Was fun though.
More recently, Resistance: Fall of Man. LAARK.
For those who don't know, the LAARK is R:FOM's rocket launcher. Pressing fire normally gives you a powerful area effect shot capable of instant-killing with a near miss. While this projectile is in the air, pressing secondary fire will slow down or stop it (pressure sensitive) and let you re-aim with a laser sight from the launcher. Good if your target moved effectively or you suck at aiming. If you press and hold the fire button while the missile is stopped, it launches guided submunitions which spiral off into the nearest wall if nobody's close, or take off almost a quarter of a player's health each if there's someone close. Alternatively, if you're holding fire while it's moving, nothing happens until impact, at which time it launches ALL of them at once. I've killed an entire 8 player opposing team in one shot with this before. There's a reason you only get 2 shots per spawn of the thing. It helps that some people don't know how to use submunitions (even when it's in the manual and the in-game description of the weapon)
Ultimate noobtube?
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