Some of the most fun to be had in clumsy ninja is when you experiment with new items and new combinations of items. The set missions will provide you with much of this, but don't be afraid to try different combinations of objects, Potions and props like Balloons. Not only will these result in some hilarious scenes involving your ninja, but you will likely receive a not insignificant amount of XP as a reward for using them.
Don't overlook the less glamorous items. Balloons, crates, barrels and Platforms can really impact on the diversity of your ninja's training regime, and while they will never earn you as much as the more traditional items that you can level up on, they are necessary to help maintain your enjoyment and keep things from getting stale. If you are training on 5 Trampolines each day you may well find yourself losing interest.
You can't hurt your ninja, so feel free to throw him, push him, pull him, tap him, and generally be horrible to him. By performing these tasks you may find you've discovered new interactions and ways to help your ninja improve his balance and control. Also, as your ninja levels up you will notice differences in how he interacts with items in the arena and reacts to objects in the game world.
Note: Use the paint brush icon at the far right of the menu to clear the arena if you have placed too many items, or items you don't want to use
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