its been a while! --slash 4x4 problems--

[brainanator]

Smoke usually means dead, and it came from the esc, so I would say it's a dead esc. But I think you might be well on your way to frying some batteries too! Good Luck!

Any other ESCs/motors to test with, you have to start eliminating variables if you want to find out for sure what's wrong, ignoring the smoke part of course.