The Chicken Caesar "Eggsclusive" is a set of six rooster cards to add into your game, replacing other rooster cards.
This was a exclusive bonus stretch goal for Kickstarter backers. It has no game effect, and is just variant artwork to add a little variety and humor. They replace any of the normal rooster family cards.
The cards are: Dormitator I, Magus I, Cucullo I, Abus I, Plusho I, Baro I. They either are themed for historical or famous people or characters (Abus - Abe Lincoln, Baro - Red Baron) or visual puns (Plusho - a plush doll chicken).
Stevus I, possibly a reference to a real world person, was removed on advice of legal counsel, and replaced with one of the above.