Elven Chess
is a Chess variant on a 10x10 board that features four new pieces next to the usual FIDE set.
All the new pieces have the move of a King.
The Elf and Goblin can move in addition as Bishop and Rook, respectively,
while the Dwarf has no other moves (but is not royal).
The Warlock can in addition move as a King twice per turn, and can do the second move even if the first one was a capture.
It can even 'tunnel' through occupied squares with its first move, without disturbing occupants of those squares.
So it is a very strong piece, worth more than 1.5 Queen.
There is a rule to prevent easy trading of the Warlocks:
if two Warlocks are captured in adjacent turns, the game ends immediately.
If the recapture takes place on the same square, the recapturer wins.
(Even if he put his own King in check by that recapture!
So never capture a protected Warlock.)
If it takes place on another square the recapturer loses.
Pawns can promote to Queen, Rook, Knight or Bishop when they reach the last three (!) ranks of the board.
They cannot promote to Drawf, Elf, Goblin or Warlock.
Pawns have initial double-push and en-passant capture as in orthodox Chess.
In castling the King moves three steps towards the Rook.
Less...