OK, lets see. Tactics will be for the Gauntlet, then the Trial provided I get that far.

MEGA MASHER
Gauntlet: Go down the centre route. Push the obstacles away, then turn and drive disc first up the see-saw.
Trial: Just plough ramp first into whoever Im fighting, and hopefully beach them.

LEPROSY INFECTION
Gauntlet: Being small and low, he can handle the left-hand route.
Trial: I may have to use tactics here. Keep the drum locked so that the teeth literally form a scoop, then use that.

CYCLONE FORCE
Gauntlet: Charge straight down the middle route. Front on, then back on.
Trial: Charge again.

AXE-O-LOTL
Gauntlet: Im going to say go down the centre route again.
Trial: Just play nagociations (or however the heck you spell it). If a house robot comes near, ram it, or hit it.