The tower is the focus of the aptly-named Chapter 5: Tower of Thunder.
In Chapter 5, Lucas and friends infiltrate the tower, but not before making the Pigmasks believe Lucas is actually the Masked Man, their commander. The party ascends the Thunder Tower, but before the climb truly begins, they are confronted by the Pork Trooper. He challenges them and loses, but he remains unashamed, as the identity of the Pigmasks' "commander" is exposed to be no more than Lucas in disguise.
The party is chased through the tower by Fassad and two other Pigmasks. Along the way, they pass through a playroom that belongs to "King P", and Lucas is struck by lightning from one of the generators, granting him a new skill. They finally come upon the tower's main generator, where a robot guarding it concludes they are a threat, and another battle ensues.
Reaching the top of Thunder Tower, Lucas and friends encounter Fassad once again. Since the tower is no longer usable now that Mr. Genetor has been defeated, Fassad decides to blow up the tower and kill the heroes simutaneously, and attempts to escape using an airship. The confrontation is made short when the tower shakes and causes Fassad to slip on his own banana peel, falling from the tower's summit.
When the airship flies by, Duster grabs the ladder with the help of Rope Snake. However, as everyone is grabbing hold of Duster, Rope Snake cannot support the mass of four individuals; he loses his grip and the party falls to the earth far below.
Along the way to the top, the party will pass through a playroom, filled to the brims with several toys, including a teddy bear, a train set, a music box, and a wrapped present that contains an unpleasant surprise.
A yo-yo rests in a trophy case near the exit. Examining it causes a robot maid named Li'l Miss Marshmallow to appear. She reveals that the room belongs to "King P", and that she must punish Lucas and friends for touching King P's personal yo-yo. Defeating her allows them to take the yo-yo for themselves.