any way to treat target (of spells) as undead?

[zza ni]

hi all. i am looking for a feat\class ability\spell\whatever that might help treating a target as an undead (for a specific spell).
was looking at Shoki's Argument and thinking how nice it would be to be able to effect other targets beside undead.
i know of many ways to count urself as undead, but is there something to treat others the same way?

[Tyrant Lizard King]

Best I can find is hitting an opponent with Bestow Curse. The GM may allow similar effects to those described in the spell description and you'll have to see if they would allow the curse effect "target is harmed by positive energy as if they were undead".

I know this walks a fine line between Advice and Rules but the "GM may allow" clause in the spell is technically a rule via spell description. Thereby, with approval, you could harm a living creature with Disrupt Undead as the spell states it fires a beam of positive energy.

[Firebug]

The Undead subdomain almost works, but Disrupt Undead doesn't technically deal damage or heal based on positive or negative effect.

If you could give someone a Corruption, but not sure how.