Muddy water only picks up electricity when the field becomes short-circuit (lights are off) and your issue is with the fact the field begins as factory (lights on). If you want to utilize that, I suggest using Noibat as bait to trigger the A.I. into using discharge as you swap into Graveler. This should shut the lights off and cause him to use earth power, however, so your graveler needs to be faster than Muk to get the supereffective hit. If you haven't already, there is a man in North Obsidia who sells you a link stone and that would allow you to evolve Graveler into Golem, powering it up su