Dirty Blood: You are death immune and appear as royal to investigative checks.
Usurper: During the King election, votes for you will be multiplied by the number of Kings you have successfully killed. (starting at 1x, so if you kill one king you get 2x which is royal blood, 2 kings 3x, etc.)
Bribe (1 use): Your attack will bypass the Kings guards tonight.
Silence (2 use): Silence a player for 20 seconds
Blood Test (inf use): Check if a player has Royal Blood or is the King. If they are you will attack them tonight. They can not be healed. Cannot be used on the same target twice in a row.
Mimicry (inf use): Use the first ability of the last Non-Unique class with Royal Blood that you killed.
Win condition: Become King and survive until the end of the game.
Basically my Pretender suggestion from my big balance patch, but as a standalone version