Is this something that you GM's out there would let your players do? And, would the CR -1 allow someone to, say, create a 10th level character in a 9th level campaign?
I am talking about this young template:
"Simple Template: Young (CR –1)
Creatures with the young template are immature specimens of the base creature. You can also use this simple template to easily create a smaller variant of a monster. This template cannot be applied to creatures that increase in power through aging or feeding (such as dragons or barghests) or creatures that are Fine-sized.
Quick Rules: +2 to all Dex-based rolls, –2 on all other rolls, –2 hp/HD.
Rebuild Rules: Size decrease by one category; AC reduce natural armor by –2 (minimum +0); Attacks decrease damage dice by 1 step; Ability Scores –4 Strength, –4 Con, +4 size bonus to Dex."
