The Kameks appear. Kamek says no more dirty tricks. Paper Kamek says they'll give the bros an honest fight. Kamek then uses magic, wondering if the bros really believed them. They fly off to set up another dirty trick. Walk forward and they'll attack. They'll do an attack where they form a line of magic and move around with it. The bros have to jump over the line, like in the Border Jump challenge in Superstar Saga. They'll also move through portals, even going back through portals. Jump to dodge or counter. Kamek will inactivate some Action Commands. They'll return after a turn. Paper Kamek will copy himself and form a moving wall to shield Kamek while he readies his magic. Use the Boomerang Dodge to hit Kamek as much as possible. They can also summon other enemies. Leave at least one Paper Dry Bone on the field so they don't summon more. As with before, you may want to just battle with Paper Mario. The Kameks won't heal each other, but Kamek will revive Paper Kamek if he falls. If the one is down, the other will shoot magic at the bros. Counter with the hammer. Keep healed and they'll eventually be defeated.
Kamek had a good time with Paper Kamek. Paper Kamek agrees that they weren't a terrible team. Kamek thinks Paper Kamek was like a hideously ugly brother to him. Paper Kamek reminds him they're identical. They start arguing. The Marios stomp them to defeat them. Go north. The area is crawling with Mechakoopas. An eerie glow comes through the windows. Go to the southeast and southwest for more items and coins. Use the warp pipe if you need better gear or more items. Save and go north through the ominous doorway. At the end of the long path, Bowser and Paper Bowser await.
Head down the path and minions will attack. They're easy to defeat, especially with a Trio Attack, but you may want to save your BP. After each battle, you'll automatically move forward. Bowser notes this plan isn't working. His answer is more minions. After the next wave, Paper Bowser calls the bros stubborn. The enemies start getting more challenging when you deal with the Shy Guys. The Bowsers try to outdo each other with their hatred for the bros.
After the Broozers, Bowser calls in the Koopalings. You'll battle them two at a time. Wendy and Roy are first. The attacks are the same. After you defeat them, Ludwig appoints himself as leader, but the other Koopalings are upset because there wasn't a vote. They then focus on the task at hand. Ludwig and Larry are next. They have new Battle Cards this time, including one that can shrink the bros. Take one out to keep them from using the Battle Cards. Make sure you're fully healed at the end of this fight. After the battle, Ludwig says he's been dethroned. Larry doesn't like that Ludwig thinks of himself as a king. Iggy, Lemmy, and Morton are last. They think the bros are tired after all these battles. Morton uses magic to mess with the bros' battle cards. The bros are okay with this. Lemmy dances off to do something. He rolls in a giant ball. Use the Boomerang Dodge to hit Lemmy before he can throw bombs. If your dodge is successful, he'll be dizzy. Iggy will bring in a giant Chain Chomp. Use the Airplane Dodge when Iggy gets close and tries to hit a bro. He'll be dizzy after the attack. Morton tries to avenge them and picks up the Chomp. Use the Trampoline Dodge. They'll all be stunned after the battle, so hit them with your best attacks. They may be knocked down, but unless all are down, they can revive each other. If your dodges are strong enough, they'll only attack twice before they're defeated. Morton asks for Bowser's forgiveness. Iggy asks the same, but for him also to destroy the bros. Lemmy asks the same.
Paper Bowser is annoyed that they must do everything. Their section flies off. Starlow congratulates them on defeating all of Bowser's minions. The bros are ready to fight. Heal, change your gear if necessary, and check out the Battle Cards you've earned, then save. Head out to deal with the Bowsers.