Sumo: Vomit (bananas are free - kick them off the ostrich landing zone) in front of door many times (abuses AStr and LStr) or throw a bottle of acid at the door, or pile some bear traps in front of door (works well if you know loricatus to fix/harden traps), and or haste yourself for fight, or fight as werewolf, or train AStr + Dex in UT to 15 each for simple win.
If you use the bear trap method and happen to have some good traps (eg meteoric steel or better ) you can also kill Decos. He comes to watch the fight so line his path with traps. pray to loricatus to fix you best broken trap. just kee reusing them once he escapes. if he loses a couple legs then he is easily killed by bear traps. Rolling Richel
I should add this is worthwhile for two mithril boots of kicking, a mithril chain mail and two ommel hair whips +3. Plus gems