Like Behemoth Chess, but the pieces killed by the Behemoth are returned to the players owning them. They can be dropped later, like in Loop chess, instead of a normal move. This is also valid for the Kings. If a player has the King in hand, they must drop the king first, before any other move. The game is won by capturing the opponent's King with an own piece.
I expect this to reduce the random factor, because the game is not over if the Behemoth kills some King, what happens frequently.
The pieces captured normally can be taken out of the game, to allow for endgames with few material, or given to the player capturing them, like in Loop Chess.