UFC 2009 Undisputed
30 Achievements
1000
Xbox 360
Pound-for-Pound Champion
Win the UFC Championship in each weight class in Career Mode.
100
How to unlock the Pound-for-Pound Champion achievement in UFC 2009 Undisputed - Definitive Guide
The championship comes about 12 matches into your career (if you go undefeated). Do this with every weight class and the achievement should unlock. Their are 5 weight class divisions and the title must be won with a created character in all of them.