JUJU

The first time round you want to ground slam on the left and right water taps. Doing so, Octobos will get out a straw and blow out water you can jump on for one of the higher two taps. Avoid the hungry piranhas that Octobos summons by jumping over them, they can't be avoided in the water. He will then blow through his straw again letting you ground slam the water tap you missed.

You'll then be flushed down further into the stage, where you'll want to again ground slam the 2 ground level water taps, but this time avoiding the piranhas. Octobos then sucks in the water allowing you to get the water taps beneath the water. Repeat this process until each top water tap is completely removed. Then repeat solely for the remaining lower taps, still whilst avoiding the occasional piranhas.

Once all the taps are removed you'll enter one final whirlpool and be on dry land, except Octobos is moving in the walls towards you. Slam on to his tentacles when he throws them at you 4 times and your first battle is complete and you'll earn the ability to swim underwater:

For his second battle, swim up to the surface while dodging his tentacles. Once up on a platform, dodge the piranhas and avoid the sea crustaceans that come up to the platforms. Jump over to either the left or right plug and ground slam on it. Avoid another piranha wave and he'll press a red button to release a few airborne bombs that can be avoided either on ground level or by jumping into the sea. Avoid one last piranha wave and ground slam the remaining plug.

You'll then be brought with the water to the next area where again you evade the airborne bombs. Now he'll shake a submarine that drops heat seeking missiles. Get them to hit his left and right grabbed tentacles to loosen his grip and initiate the final part.

Once you've risen you will want to avoid the water blasts as you make your way to the surface. Avoid the piranhas as you simply ground slam each of the 2 plugs. This will make Octobos lift up some tentacles to prevent the netted bag of bombs dropping on him. From the sky a tribal statue will come down, use to get him to cause Octobos to lose his grip and turn back to an ordinary octopus. Earning you this trophy and your third key part: