The way forward is now clear. Before you go north, walk to the south to lower the other drawbridge. There are Piranha Plants here. Walk to the east, near the stone brick block and Wiggler will show the bros another electrified gate. This one has two generators to destroy. The path to the one on the left has a lot of mud, so you'll have to move quickly. For the one on the right, walk up the ramp to the Bomb Bud, then walk up and off the ramp. Use the northern most orange spring to reach the stump you need and throw the Bomb Bud. Wiggler goes on ahead to see if there's more trash. Go west to get a few items, then try to go north.
Kamek appears and places a force field on the path ahead. He is offended when Starlow refers to him as the "non-paper version". He will attack the bros. If the bros are hit three times, it's over. Grab Bomb Buds to throw at Kamek. He'll be moving around, so time your throws. After the first hit, he'll use a force field to defend against Bomb Buds. Starlow notices the force field lowers right as he's about to use his magic. The timing is tricky for this one. The next time, he'll make two copies of himself. Keep track of them as they move, then throw the Bomb Bud when they move backwards. After this, Kamek vows they haven't seen the last of him and flies off. The force field disappears. Starlow notes that Kamek is trying very hard to keep them from Mount Brrr and wonders why.
There's a Lakitu Info Center here, but no new quests. There's a challenge board with prizes for clearing enough challenges. Talk to the other Lakitu at the desk to clear more challenges. The prize for clearing 20 challenges is a Battle Card. Walk to the north and you'll find Wiggler confronting Paper Kamek about littering the forest. Paper Kamek calls him an irritating insect and zaps him with magic, enraging him. He convinces Wiggler that the bros are the enemies and he attacks.
Wiggler charges his attack power and slams onto the ground, unleashing two shock waves. Afterwards, he'll target a bro and spit a seed at them (or more if he's aiming for Paper Mario). He'll then chase a bro, who has to clear out the obstacles with his hammer. Paper Kamek is also part of the battle. He'll give Wiggler a giant paper ball to run on. Paper Mario folds into a boomerang for the Boomerang Guard. Aim at the ball and throw the boomerang back and forth. The ball will move, so keep aiming. Paper Spear Guys will also join the battle. Paper Kamek may also attack with magic. Counter with the hammer and it will hit Wiggler. If you're going to use a Trio Attack, use Trio Kite. Trio Racquet allows you to hit the segments, which won't do any damage. After enough damage, Wiggler will return to normal and you can battle Paper Kamek directly. After a while, he'll revive Wiggler. It is possible that Paper Kamek will fall before Wiggler does due to counterattacks. If so, Wiggler will return to normal and the battle will end.
The bros haven't seen the last of Paper Kamek, according to him. Wiggler doesn't know what got into him, but thanks the bros for snapping him out of it. He's feeling very tired, however. He collapses. Paragoombas appear and carry him off. The bros are sad, until he asks them why. Wiggler reappears as a butterfly, Flutter. He flies them to Mount Brrr.