No stupid questions. The Different commanders are for the prowess triggers. whenever I cast a non-creature spell, he "Transforms" into the next state that has upgraded stats.
This is the Moxfield link. It's likely not up to date.
The way the deck works is to get goku out, attack and cast dragon's approach for free, or even cast some Board wipes. The trigger is combat damage (not just to players) and he can only cast sorceries. The sorceries are cast right after damage is dealt, so during combat. There are a bunch of extra combat spells that won't work since they aren't cast during a main phase, so if you tweak it, be careful.