Tower of Yikk
The Tower of Yikk is first discovered by Bowser while he is searching for the first Star Cure. On his way to Dimble Wood to confront Durmite (who is not there, unbeknownst to Bowser), he passes a propeller protruding from the surface of Blubble Lake. The Koopa King takes advantage of an allergy to a nearby plant, activating the propeller with a sneeze. This causes the submerged tower to come to life, escaping from the lake and crushing Bowser beneath a mechanical leg. Traveling to the Rump Command again, the Mario brothers activate Bowser's ability to grow to match the size of the tower. He defeats it by punching it into the lake, and then punching the tower's head, its weak spot. Bowser's strength is able to deactivate the tower permanently, allowing him access.
Inside the tower is a Save Block and a Shop Block. A short hallway and an elevator ride lead to what appears to be some sort of study. Here, the door locks behind Bowser. The spirit of Yikk appears and shows Bowser the Boo-ray Machine, which allows the Mario Bros. to pursue Durmite.
The top of the Tower of Yikk can be seen on the map screen (as shown in the bottom right image).
The Tower of Yikk has various moves. One of its moves is having Mawful Moles with Hammers jump on its head, forcing the player to use the flame to prevent them from restoring a chunk of its health. Another is having Crawfuls throw a Fawful Bomb at Bowser. Bowser must punch the bomb back and forth, and if it lands below the tower's head, it'll explode. Unfortunately, in the very same case Bowser can be helplessly pushed back by the move if vice versa (the tower headbutts the bomb very low). Its other move will involve Leaf Guys flying at Bowser with giant, ready-for-ignition bombs, which involve fireballs to take out. Sometimes, they'll send Refreshrooms for later use.
If the tower is pushed into Blubble Lake, it'll attempt to fly back up on solid ground. Bowser must punch repeatedly (by touching in a small area) to prevent that from happening. Right after the second attempt, however, it'll succeed, no matter how fast the player is tapping.
If Bowser is pushed into Blubble Lake, he'll be temporarily stuck and the tower will jump on his head twice for a large amount of damage.
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