How can I make a realistic collision bounds in BGE? I have a planet and I want it to have some terrain, like mountains where the character can explore. I need the planet to have realistic collision bounds, but triangle mesh makes it act like a "No Collision" object, and also it makes the game extremely slow. How can I make realistic collision bounds without slowing the game down?
I have found that if I were to have a mesh with a tri count of greater than about 1.5 million (at least on my machine, could be different for you due to differing PC specs on your end) set to triangle mesh it would produce the same results.  Lower the poly count and try it again to see if that is the issue.