* '''Polymorph''' - [[Polymorph]] yourself into a more powerful creature
* '''Trap''' - Place a [[bear trap]] or [[mine]] in front of the sumo's house, and lay some bananas behind it to tempt him. He will come over to eat the bananas, and probably get wounded or even dismembered from your trap. Just make sure that you don't kill him on accident and that you place the trap outside of his house not in it.
*'''Trap the arena''' - If you are invisible you can sneak into the arena without challenging him and rig it with traps or equipment for you to pick up and use.
It is also helpful to [[Hasted|haste]] yourself (zap with a [[wand of haste]]) so that you can move more quickly than him.