We had an interesting scenario pop up at our table. A dwarven runesmith (Races of Stone p.118) with caster level 9, getting ready for a big battle, did the following:
- He set all his equipment out on the ground so nothing would be eaten by polymorph
- He cast Polymorph and turned into a Behir
- He cast Girralon's Blessing (Spell Compendium p.106) to gain a pair of arms
- He cast Fearsome Grapple (Spell Compendium p.90) to gain 2 pairs of tentacles
- He cast Fuse Arms (Spell Compendium p.100) for +20 untyped str from the Behir's 2 extra pairs of claws + everything gained from his spells
- He then cast Alter Self and turned back into a dwarf
- He put on all his armor and cast Fist of Stone (Spell Compendium p.94) for a +6 enhancement bonus to strength
- He cast Enlarge Person on himself to become large and get +2 size bonus to strength
All told, he claimed to be a Large Dwarf with 54 strength, 11 dexterity, and 21 constitution.
To what level does this work?
The argument was that Alter Self transforms you based on your "normal form" which is a dwarf (this is based on the assumption that "normal form" is what would be seen if viewed with a True Seeing spell), but it explicitly doesn't affect any of your ability scores, which are obscenely high from the Polymorph. And since he assumed the form of that creature (a humanoid dwarf), it changed his type back from magical beast so he could still cast Enlarge Person. Is he correct?