Achevement- Breaking your toys.
I found out that the best way to do this achievement is after you have finished the main story/campaign as you will have a character better than you can in Create a fighter even with the ko artist boost dlc if you have it, but you can just make a character in CAF if you want as the achievement isnt to hard, Something that had me stumped was were my created characters were, because in every other ufc they were with all the other fighters, but not in this one, to select one of your created fighters go into there weight division(s) and when on fighter select press right or left twice and you created fighters are in there own little section, make sure the difficultly is on EXPERIENCED, its one up from BEGINNER,once you have chosen your character chose your opponent that is either the lowest rated or someone in the story that you beat easily, then ther rest is up to you, you can beat them in anyway, ko, tko, submission, decision or doc stoppage, as long as you win then the achievement will pop as soon as you win.
And on a side note, if you do use a story character and you got into the hall of fame then that sets you up for the BREAKING YOUR BEST TOYS achievement worth 30 gamerscore.
Hope this helps
o0 JdogJ 0o