Ok, how about a 5kg titanium circular saw that can retract into the body?

Intrigue vs Nitro-Gene 4.0

3..2..1..Activate!

Intrigue comes in and presses the pit release button, as Nitro-Gene gets under him, and flips him. Intrigue didnt like that, and gets around to the left of Nitro-Gene, to try and axe those wheels. He succeeds, but not without getting flipped upside-down by Nitro-Genes flipper. Intrigue now uses the axe to self right, but Nitro-Gene is prepared to flip him once more. Intrigue now pushes Nitro-Gene onto the flame grill, and now into the angle grinder. Nitro-Gene is not moving, so our special guest refbot, The Watcher, will now count out Nitro-Gene.
1..2..3..4..5..6..7..8..9..10!
Nitro-Gene 4.0 is out, which means Intrigue wins this demo match.

How about that?