Become a Prizefighter

Become a Prizefighter is a quest in Fallout 2.

Quick walkthrough
Beat all the contestants at boxing.

If you go into the Jungle Gym and talk to Stuart Little you can box. If you are female or have STR<6, you'll have to pass a relatively easy Speech check. You'll meet four increasingly difficult opponents: Joqq ($50, 500 xp), Pete McKneely ($50, 750 xp), Evan Holyfeld ($400, 1000 xp), and the Masticator ($1000, 2500 xp). This is assuming you get 50% of the winnings; with Speech 76% and Barter 76% you can get 75% instead. You also get kill xp for those boxers you manage to beat to death; this should happen some of the time and counts as a knockout. Other ways of winning include "normal" knockout (if you score a critical hit that knocks your opponent unconscious or if he himself manages a critical failure), technical knockout (if you make him flee), and points (if you somehow manage to make a fight last 12 full rounds and win the majority of them by landing more punches than your opponent). If you win four matches you get the Prizefighter reputation which lets you empty the gym lockers, makes you popular in New Reno and gives you a +5% bonus to your Unarmed skill.

Should you lose a fight, you must ask Little for a rematch immediately or you won't get another chance. You'll then go up against another boxer (your royalties will drop to 25%, but the xp is the same). You can only convince Little to give you one more chance (unless you exploit a bug, see note below), which means you can fight five matches in all, and there's a tempting reason to do that (see another note below).