Mighty Flip Champs!
When I bought Shantae: Risky's Revenge from the DSi store, I put twenty bucks in my account, because the game cost twelve and the next smaller payable increment was ten. That left my balance at eight, money I didn't spend until recently, when I decided to get Mighty Flip Champs, the first DSi release by the same team that made Shantae. I didn't like it quite as much, but it still provided several hours of entertaining, mind-bending puzzles.
The game doesn't really have a story, beyond the very basic premise of a girl and her animal companions traveling through dimensions or something. It's just there to set up the puzzles, which place you in a room, where you have to gather all of the other animals and then get to the frog to win, and get to the next stage. The twist is that each stage has multiple layers to flip through, all with small differences that you need to exploit to get to the end. So one layer might have a dead end, but flipping to the next one might open up a hole that lets you through. It starts pretty simply, but the game ramps up the difficulty quickly, tossing in new elements and increasing the complexity until you get to some really tricky situations. You are timed on every stage and challenged to get the best time possible, and if you touch any spikes or accidentally flip your way into a wall, you have to start over.
There's a really nice balance between challenge and player friendliness, as I only got really frustrated a couple times. Usually the game requires you to think without stumping you too badly. The slow drip of new toys like color coded blocks that can be altered by switches and portals from one place to another keep things constantly fresh. And if a puzzle does annoy you, there's a good chance the next one will be a bit easier on you, or at least switch to a kind of challenge you're better suited for. There's a total of 41 stages, including five that have the level do the flipping for you on a timer, which plays to a slightly different skill set, and a final monster of a level that tests everything you've learned. It's a nice package, with certainly enough content and incentive to replay levels to be worth the eight dollars. It's got a nice look and some surprisingly catchy music too, so it's hard to find much fault with the game in any area. Definitely a pleasant way to use up a leftover balance.