Mario Kart Advance
Before this excellent handheld racer was installed with scaled-down versions of the N64 game's pre-rendered character sprites, the drivers were going to have a super-deformed look with immensely huge heads. The original graphics survive only in the very first screenshots and the odd snippet of E3 video.
Star Fox 64
A beta video shows an alternative version of the opening Corneria level. It's greatly simplified and looks to be covered in snow - either that or they hadn't got round to drawing the grass textures yet. Moving at a greater lick than the finished game ever did, it also features the robot boss running away from Foxy and friends in a linear version of the finished product's All-Range mode.See for yourself.
Wind Waker
There's an entire test area hidden inside every copy of Wind Waker. With the correct Action Replay codes activated, Link can explore several variants of a strange room covered in checkered tiles. There are items to use, pools of water to swim in and various traps to experiment with. It's one of the more surreal examples of development leftovers.
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