Any way to add more types to a Dybbuk's Corspe Possession ability?

[ksbsnowowl]

Corpse Possession (Su): A dybbuk that enters a square occupied by a corpse can, as a standard action, possess the body. It can only possess bodies of creatures of the following types: animal, humanoid, magical beast, monstrous humanoid, and vermin. The body cannot be headless or destroyed beyond recognition, and a dybbuk cannot possess a corpse in the area of a magic circle against chaos, magic circle against evil, or a similar effect.
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I highly doubt there is anything that will help me out, but I'm wondering if there is any rules-legal way to add to that list of creature types?

[awaken_D_M_golem]

PAO could change the creature type.
2nd PAO to maintain the new type.
Either way seems expensive, though maybe useful.

T.O.-ish usage ... there're rumors of ways
to get Templates, but the immediate response
is (quoting PhaeXY):  "That way lies madness!"
idk, I'm suspicious it may have popped up in
the old pun-pun, and maybe the newer one.

[ksbsnowowl]

Wait, corpses are objects, right?

Fiend of Possession can possess an object.  Is there any reason that shouldn't work for my purposes?

[Nunkuruji]

Love that ability, the horror and laughter of my players as it slayed and possessed their knight of the weave. Fantastic defensive capabilities across the board.

[ksbsnowowl]

Well, looking more closely at Fiend of Possession, it works, but not as completely as one would hope.

The fiend is aware of what is going on around the object: It can see and hear up to 60 feet away as if using its normal senses (it does not gain blindsight).
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While possessing an object, a fiend of possession can use any ability it has that requires no physical action, such as using a spell-like ability or telepathy. It cannot cast spells (since it can neither speak nor move), attack physically, or perform any other physical action, until it reaches a high enough level to make the possessed object perform these tasks for it.

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Control Object (Su): When possessing an object with some inherent mobility, a fiend of possession of at least 3rd level can control the object’s movement. The fiend can cause a vehicle or similar object to move at a speed up to the fiend’s own land speed in its corporeal form. Other moving parts—such as a clock’s hands or a crossbow’s firing mechanism—are under the fiend’s control. Thus, a fiend could make a wagon steer toward a pedestrian, or roll out of a stable without a horse to pull it. It could make a crossbow cock and fire (but not aim or load itself ). Exerting control is itself a free action, though actually moving an object requires a move action.
Animate Object (Su): At 4th level, a fiend of possession gains the ability to force an object with no inherent moving parts to animate, effectively animating it as with the animate objects spell. See the description of animated objects in the Monster Manual. At this level, a fiend of possession can also possess (and animate) Gargantuan objects.

Nothing in the Control Object ability allows the FoP to attack with the object, though it does mention steering toward targets, so it wouldn't be unreasonable to allow it to attack with a troll's claws at 3rd level.

Alternately, one could interpret it as not allowing attacks until it gains Animate Object, which directs you to the animated objects stats in the MM, thus actually granting attacks and stats for the corpse.  Also, the FoP's senses are severely restricted inside a corpse (60 feet).

Not perfect, but it's doable...