Fight kiln glitch

Well I don’t know if anyone else is having the same problem as me but if you are please post!

Anyways, whenever I get to wave 35 the Runescape Gold game always crashes. It has happened twice now. I know two time could just be a coincidence but the second time the screen went black and a message showed up saying “Java platform error”. Then i log back in and am dead.

This really just makes me mad. Please post if you have anything to say or are having the same problem.