Riders Downhill Racing gives you several vehicle types — ATVs, cross bikes and speed boats — across three modes: free ride, race and career, each playable solo or two-player on one keyboard.
Free ride is where the diamonds are, and diamonds unlock items, so it's worth spending time there before racing rather than after.
ATVs, cross bikes and speed boats, switchable with Tab, each suited to different terrain.
Yes — on one keyboard, with Player 1 on W A S D and Player 2 on the arrow keys.
Slowing your descent on big drops so you land flat rather than nose-first.