Great Mahjong

Your goal is to maximize your score while completing your puzzle

Select two identical tiles to remove them from the play field. Remove all tiles to complete the game. To select a tile, the tile must have either its right or legt site completely open and there cannot be any tiles on top of it, or even partially on top of it.
Use your MOUSE

Defend your Mars base and eliminate all alien ships - avoid friendly fire at all cost!