Achan hiArusa
Explorer
I would just start everyone out as a 1st level commoner with hit points rolled. Then they could advance to apprentice levels from the 3.0 DMG. And then finally I would give them their class level. I would just dip into negative xps so to go from commoner to apprentice would be -1000 xp and from apprentice to level would be -500 xp.
So
Level
-1 -1500 xp Commoner
0 -500 xp Apprentice
And then just give them scads of action points to survive if you want them to.
So
Level
-1 -1500 xp Commoner
0 -500 xp Apprentice
And then just give them scads of action points to survive if you want them to.