Merge Defense brings together the action of a tower defense game with the puzzle of a merging game. The goal in the game is to stop all of the monsters from reaching the end by shooting them from the tanks. The tanks will auto fire. Place them strategically so their shots are within range of the enemies. Merge together two same level tanks into one stronger tank with the next level. Use power ups such as double shooting speed, slow enemy speed and double gold. There are many tasks and quests to complete, and achievements to earn.