Which creatures are immune to non-lethal damage?

[Rycaut]

I'm thinking about building a non-lethal specialist for PFS play (all melee or spells from this character would be non-lethal - via merciful spell, feats/racial abilities etc)

But I know as a DM I've seen a few monsters that were immune to non-lethal but at the moment I can't recall which.

[Mortalis]

Off the top of my head, undead, constructs, and oozes. Possibly aberrations, but probably not.