Undead Anatomy II

Transmutation (Polymorph)
Level: Alchemist* 5, Magus * 5, Sorcerer */Wizard * 5
Components: V, S, M (a piece of the creature whose form you plan to assume)
Casting Time: 1 Standard Action
Range: personal
Target: you
Duration: 1 minute/level (D)
Saving Throw: -
Spell Resistance: -
  This spell functions as undead anatomy I, except it also allows you to assume the form of a Tiny or Large corporeal creature of the undead type. If the form you assume has any of the following abilities, you gain the listed ability: climb 60 feet, fly 60 feet (good maneuverability), swim 60 feet, Darkvision 60 feet, Low-Light Vision, blood drain, DR 5/bludgeoning, Scent, freeze, Grab, mimicry, Pounce, shadowless, sound mimicry, and Trip.
  In this form, you gain a +4 bonus on saves against mindaffecting effects, disease, poison, sleep, and stunning. If the form has a vulnerability to an attack (such as sunlight), you gain that vulnerability.
  Tiny undead: If the form you take is that of a Tiny undead, you gain a +4 size bonus to your Dexterity, a -2 penalty to your Strength, and a +1 Natural Armor Bonus.
  Large undead: If the form you take is that of a Large undead, you gain a +4 size bonus to your Strength, a -2 penalty to your Dexterity, and a +4 Natural Armor Bonus.