I love this kind of stuff. Here you go
(Pawn) Squire= move forward or sideways 1 square. can only capture forward 1 square.
(Bishop) Summoner= Moves diagonally 1 square. Friendly pieces may instantly move to an unoccupied square adjacent to the Summoner. (counts as a move. Cannot summon the King.)
(Knight) Teutonic Knight= Moves as a Standard Knight, captures as a standard King. Pieces more than two squares away cannot capture the Teutonic Knight.
(Rook) Dragoon= Captures 2 squares forward and backwards. Moves as a Standard Bishop. When a Dragoon captures an enemy piece it immediately returns to the square it attacked from.
(Queen) Iron Queen= Moves/Captures as a standard Queen. Can only capture the enemy King or be captured by the enemy King.
(King) Kaiser= Moves/Captures one square orthogonally and backwards as a Knight. Kaiser has the option to WILD ATTACK capturing all adjacent friendly and enemy pieces.
Post variants here. If you want I will hold a contest of the best variant.