Test of Vengeance
Jake Kabrinski takes on a Draconis Combine Atlas one on one. He jets up to it, only to be swatted with an Atlas punch. Unfortunately, the Atlas falls down due to the swing. When the mech gets back up the pilot learns to his horror that Jake is on the back armor firing away. After a futile use of the rear mounted Medium Lasers, the pilots gets a brilliant idea: fall backwards. So he jams the foot pedals and causes his Mech to fall on it's back to crush the Elemental. Almost worked, but unfortunately when the pilot regained consciousness, he saw a very battered Jake blast through his cockpit and stab him with the claw.
Elemental 1, Mech 0. Better luck next time!