Seriously, I am just confused bigtime. Not a single thread has been of any help to me, I don't get how it's so hard to just answer lol. I've also wandered the entire map 70 times. I am at the swamp with all the lightning stuff, still lacking lightning power.
I read something about proceeding without the power, but I just can't see any way. :(
According to the walkthrough at http://members.ziggo.nl/tonnessen/MF%20tangaloa%20swamp%20moving%20bridges.htm you need to go through "tangalo’a swamp moving bridges." At the far end is a boulder blocking the path. You need to get Majin over there to break it.
Within the swamp, there is a courtyard type area that is filled with darkness enemies, switches and platforms. You might think "Huh, well can't do anything here.", when actually, you need to go through here.
Go into the central area and defeat all the enemies. You will find a set of ledges with a large boulder on top. Simply climb up here and make Majin break through it. Beyond here you will find Lightning.