Chess is a familiar game to many people. Even if you don't know how to play, probably know there are pieces like the knight or the queen.
A group of enemies based around chess pieces make a great group of enemies. You have a group of enemies that all work together as a unit, and their visual appearance and mechanics reinforce their chess-game roles.
You could have a tinkerer or wizard called "The Grandmaster" who has created robotic servants and guardians. These Chessmen work great for a short arc, but watch out for the queen!
Enjoy the Chessmen!