When you pick the speed perks and you choose to keep playing in sandbox mode, pick the spikes perk, because after a while you are able to speed up enough to fly too!
I just found a cheat. when the screen "says" go! then u have to pull the "watch bar" (if u dont know what i mean, the bar at the bottom of the screen) far into the right and dont drop it. ur animal races then at top speed :D
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