You take death and wrap it about you like a cloak-your colors wash out and your skin grows cold to the touch. Your heartbeat, breathing, and similar life functions become very difficult to detect. Senses such as lifesense detect you as undead unless a creature succeeds at a Perception check against the spell's DC, and on a failed check, they don't detect you at all if they only sense living creatures. Detection spells that specifically sense living creatures must succeed at a counteract check against mimic undead to detect you. You gain a +4 status bonus to Impersonate an undead but physically intact version of yourself and can add your level as your proficiency bonus even if you're untrained. You don't gain these benefits to Impersonate any other sort of undead. Mindless undead usually don't have a reason to even attempt the Perception check to notice your Impersonation unless you interact with them in some way.
Spell Effect: Mimic Undead
Traits
An action with this trait requires a degree of mental concentration and discipline.
You must physically manipulate an item or make gestures to use an action with this trait. Creatures without a suitable appendage can't perform actions with this trait. Manipulate actions often trigger reactions.