×I know that you have to get the snakes to the NW corner with the gates closed, but I can't figure out how to do that. I can lead them up there, but when I go to close the gates, they follow me. Closing the gates first make it impossible to get them in the corner.

×I think I killed off all but one of them before trying to close the gates

×I lured the last snake through the bottom of the trap from the right, and was able to dash to below the middle of the trap so that the snake ended up turning north. Then, I just stalled for a couple of moves to get it to come back down the middle with enough time for me to hit the orb at the bottom.

×Lure one snake out at a time and close the doors again right away. Lead him towards the left wall, then with your back to the wall, step south at the last possible minute. The snake will take one more step towards the left with his head pointing towards the wall.

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Then step 1 square right and the snake almost always takes a right turn north up into the 1 wide corridor. If you step back towards the left promptly so you're behind the snake's head, he'll continue up to his death. Repeat for the other three. You don't even need the strange little three-pronged trap in the middle.