Axom

According to the creator, the name of the game has its origins in the French words : Axe [the axis] and Somme [the sum] : the deployment of a pile of piece is determined by the sum of the pieces contained in the same pile.

This means that a pile of 2/3 or 4 pieces will have different powers depending on its number of tiles and will 'break apart' accordingly.

Furthermore, it's an easy game that's also easy explainable and the rules can be found online.