I like motorcycle games..
Suggestions:
1_ Make new motorcycles (women would be nice);
2_ Implement physics to it.. not difficult, I think;
3_ Use matrixes or terrains, but they aren't everything,
you could make ramps..
4_ How about colecting rings by jumping through them?
5_ How about (with physics implemented, of course) create
a large terrain and make some rings to pass inside them in
a given time?
6_ And make a survivor mode with that..
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7_ How about adventure with some abysses to jump over in high
speed.. and some rocks in the road? (rings in some point of the
abysses.. the rings (color differed) could give powerUps.. such
as extra time, change FOV, speed, jumping height...)
8_ Or many walls to pass through (each one with only one
hole (with different sizes in each wall) to player pass through)..
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9_ Or..
[EDIT]nope.. this last I can't tell you.. this is gonna be my
Motorcycle game
For any way you choose, good luck.. =D
The worst foe lies within the self...