In episode 5, Yuji & Co. sneak into a Blue-infested communications center to contact their space station. Midway through their call, the Blue get wise to them, and a Chopper (a giant stag beetle thing, not a helicopter) crashes through the wall and slams right into Marlene, knocking her across the room. The thing comes after Joey and Yuji next...until its core is shredded by a three round automatic burst. The guys track the shots to their source to find a very pissed-off Marlene, displaying a little bruising and a cut just under her left eye. She was body-checked by a bug the size of a car, and it just made her angry.
In the movie The Warrior, Marlene saves Yuji from a Land Whale by throwing her Shrike's giant bayoneted rifle into its mouth like a spear, then grabbing Yuji's mech's machine gun and applying More Dakka to the monster's face until it dies.