Snuck a peek on TA for help with this one. The user Visions of Gore used the following trick:
Kick an enemy (
+
) near a body of water or in front of a high ledge or an abyss, then push him off the edge with Force Push (
).
Worked for me with a Scazz. I kicked him once and then force pushed him into the water and trophy popped.
Greetz
Cap