Panfu Defence is a tower defense minigame found in Bitter Forest. It was added in september 2013, and has only 1 level.
Price: 10 coins. Comparable with the Dart Monkey from BTD. Shoots one target and takes off one layer of protection. Can be upgraded using coins, but since the game only has 1 level it's better to place 2 of these than to upgrade one.
Price: 15 coins. Comparable with the Glue Gunner from BTD. Shoots one target. Deals no damage, but slows the target down until it takes damage. Upgradable.
Price: 20 coins. Comparable with the Bomb Tower from BTD. Shoots one target and deals AOE damage. Upgradeable.