The right eye can only be killed by the adder.
×After the bombs explode, the second eye will usually be on an edge, which means the adder can eat it. You should get into a position where the adder is near the mud mother when it explodes and the mud mother has just spawned. This will give you the most amount of time to finish the mud mother off.
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×Standing at (15,13) while the adder's head is at (17,13) can be useful. Also, you can use the oremites to switch your orientation if necessary.