Goku went back in time at the start of GT into the Buu Saga. Kid Buu has just been defeated and Goku is eager to VS Mystic Gohan and SSJ3 Gotenks.
Everyone is going all out and there is no outside help.
Place takes battle on Earth (if full no-holding back battle occurs they fight in the troposphere)
Goku starts at base and can go SSJ3 (x20 Kaioken is his maximum, but can only hold it for 30 seconds).
Both Gotenks and Mystic Gohan start off at full power.
Who wins and why?
Fight until K/O, no death. No destroying Earth as well.