As an avid DBZ fan for many years owning many of the games, we all must have did something pretty great in those games.
For me, it was in Buus Fury, my 2nd ever DBZ game. (First was Budokai 1 on Gamecube, cause i didnt have a PS2 until like 3 or 4 years later. Anyway, it went like this.
In Buus Fury, you gain "stat points" each time you level up. And along with equipment, you can have a really powerful character very early in the game. However, I never knew how to use the stat points. (Now, I wasnt like 4, i was like 10, i just honestly didnt know.) I beat the ENTIRE GAME just with my base power (with equipment)..hardest game i ever played. Took me like 7-9 months to beat it..And after i beat the game, i finally learn how to upgrade myself. lol