Your goal is to climb to the top of each stage, fending off monsters and collecting bonus items along the way. The best part is that you get a grappling gun you can use to latch onto platforms and swing yourself upwards. The gun doubles as a harpoon to attack enemies and gather items, making its use a central element in the game. Each stage is filled with score-increasing items in the form of... ice cream! You can also collect letters that spell "BONUS" to get extra points at the end. The difficulty progresses fairly evenly, although it does take it some time for the stages to become a challenge. Use the first few levels to get used to the walking and grappling mechanic, as you'll need all of your skills towards the end.