3D Caveman Rocks!

Hints:
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Submitted by: rickHH

Remember, you can step on bird and rhino backs to get over deadly obstacles. 
Ride special rhinos to destroy walls that block your path. 

Be careful of the order you use keys to unlock doors, you may block your 
path if you're not careful. 

Collect bones for points, the bigger the bone the bigger the score. 

Watch out for birds that are flying high, they launch rocks! (yes, rocks, 
not what you're thinking). 

Look at the shadows on the ground to accurately judge positions. 

Rhinos know how to use elevators (just like in real life), so be careful. 

Barrels can change direction depending on the path slope, but rocks 
follow the same direction all the time. Watch out for rocks and barrels 
falling from higher altitudes.