1. Chess variants with different initial positions
These chess variants have different initial positions than chess. Otherwise the rules are the same, the table is the same, and the pieces are the same (but not necessarily in the same number).
In these variants though the initial position is not symmetric, the chances may be more or less equal. The exact number of pieces is adjustable.
White has only pawns, and Black has knights and a single pawn
These variants explicitly prefer one player (white) to equalize players with different skills.