Alter Self As An Undead Troll [PF]

[The Oni]

So I'm (unexpectedly) an Undead Troll with the power to cast Alter Self. Rules as written, what are all of my valid targets for forms?

[OldTrees1]

You assume the form of a creature of the same type as your normal form. The new form must be within one size category of your normal size. The maximum HD of an assumed form is equal to your caster level, to a maximum of 5 HD at 5th level. You can change into a member of your own kind or even into yourself.

Type: Undead
Size: Medium to Huge
HD: up to caster level(6th?) but capped at 5HD

So you could become a Vampire Owlbear(5HD) but not a Vampire Troll(6HD)
Human Lich Necromancer 5 is questionable but if they could boost their caster level by 6 without additional HD then it would be possible. I didn't keep reading the spell

[Deophaun]

So you could become a Vampire Owlbear(5HD) but not a Vampire Troll(6HD)
Vampire is a template, and

You cannot take the form of any creature with a template, even if that template doesn’t change the creature type or subtype.

Edit: I'm pretty sure Undead is the worst type there is for alter self, because the only things the different forms offer are things that alter self doesn't give you. I mean, you could turn into an Allip if you wanted a fly speed, but you aren't going to have any attacks.

[Jack_Simth]

Ummm... yeah, for the most part, you might as well ignore Alter Self. I mean, you can turn into a vampire spawn (4 HD) to look like a normal human/elf/half-elf/half-orc/other Medium humanoid, and can turn into a Wraith when you want to fly, but you don't get subtypes, so don't become incorporeal.

Undead... isn't a very good type for Alter Self.

[Deophaun]

Here's what I found going through MM2-5

Bonespur (MM V). +4 Nat AC. Large. But you have a speed of 10.
Necrosis Carnex (MM IV). +4 Nat AC. You get Mobility as a bonus feat! Yay. No attacks.
Spawn of Kyuss (MM II). A natural slam attack! +2 Nat AC. How generous.
Vasuthant (MM III). Slam attack and +3 Nat AC. Fly 30 ft (Perfect). Some racial stealth bonuses, Improved Grab and Improved Grapple! But you're small, so the last 2 wind up doing nothing. Plus I think the size differential rules this one out for you.

[The Oni]

The only reason he's got the spell in the first place is because he was originally an Oni-Spawn Tiefling, and got transferred into the troll body. DM ruled Alter Self is based on the soul and not the body so he kept the power; I'm just wondering how to make the most of it.

Also, this is Pathfinder, if that makes any difference.

[Ravens_cry]

The only reason he's got the spell in the first place is because he was originally an Oni-Spawn Tiefling, and got transferred into the troll body. DM ruled Alter Self is based on the soul and not the body so he kept the power; I'm just wondering how to make the most of it.

Also, this is Pathfinder, if that makes any difference.

Very. Pathfinder Alter Self (http://www.d20pfsrd.com/magic/all-spells/a/alter-self) explicitly turns you into a humanoid and a humanoid only, even if your type is otherwise.

[The Oni]

That seems strange and illogical. We may end up houseruling the other version.

[Ravens_cry]

That seems strange and illogical. We may end up houseruling the other version.
I'd say it's more anthrocentric, but I did thought it'd be good for dragons and other creatures who might want to pass as human. Including, say, your Troll, though it'd be better as an item as 1 minute a level is pretty short for social interactions.