Mecha Gnar.

I hope that somebody has made the connection between giant robots and a transforming champion. Mecha Gnar would be a pretty sweet addition to the project mecha bunch IMO.

A mechanical boomerang. Rocket jump. Robot voice yelling "GNAR!" Cute and deadly.
Then... steam whooshes and surrounds him as metal slides against metal fitting into place. Two glowing eyes stare back at you as indistinguishable objects twist and clank beneath the mist. The cloud disperses and you see a giant figure leap out!

MEGA MECHA GNAR emerges from the steam to smash and wreak havok! By sheer luck, or prudent strategy, he has an everlasting supply of buses to crunch into balls and hurl at enemies leaving them helpless. The mechanical wizzbangs his engineering team developed smash and crush everyone and everything in reach, the impact leaving all dazed and defenseless. On second thought, no don't do this skin... I'm already scared.