Mechawiggler is a massive insectoid robot from Super Mario Odyssey and the boss of the Metro Kingdom, as well as one of the six bosses refought at the Mushroom Kingdom. Despite being ostensibly based on a Wiggler, it bears little resemblance to them, though it has a similar "enraged" state and several segments making up its body. It has five glowing orange eyes, a cyan and pink plasma globe embedded into each segment including the head, yellow electricity-producing rods surrounding said globes, and a mouth that resembles an electric plug.
Mechawiggler is initially found covered in electricity on the lightning rod of New Donk City Hall, where it uses its plug to absorb the city's electrical power. Once Mario reaches the top, it briefly crawls around the rod a few times before stopping and shrieking, followed by it charging Mario off the side of the building. Mechawiggler then proceeds to pursue the falling Mario down the side of the building. Mario lands upright on the ground and the battle begins.
Mechawiggler attacks Mario by hurling electrical orbs from each of its segments while crawling along the wall. Mario must capture a nearby Sherm, avoid or destroy the balls of electricity, and shoot Mechawiggler's weak points, the plasma globes, which go dark, along with the electric rods, after one hit each. Once all the globes have been destroyed, Mechawiggler stops moving entirely while the globes glow faintly along the cracked surfaces, and Cappy urges Mario to start shooting at it even more, which in turn causes Mechawiggler to squirm around before eventually getting covered in miniature explosions with another shriek.
Mechawiggler then gets angry, turns orange, begins moving faster, and phases through the wall of City Hall, obscuring itself from Mario's view. However, Mechawiggler's movement inside the building is marked with a spark of electricity along the outside wall moving to the ground, followed by a large purple aura appearing for several seconds, marking Mechawiggler's point of attack. When this happens, it rushes out from the purple vortex in a straight line at an immense speed along the ground. Mechawiggler continues this attack pattern through various surrounding walls a few times, before going back onto a wall, still angry, and shooting four electric spheres. After this, it calms down, and its plasma globes relight, now a pink color. It continues crawling along, now at the same speed as during the first phase, and still shoots electric spheres. Mario must again destroy the plasma globes. However, now Mechawiggler becomes angry potentially before Mario is finished, and makes a single charge across the ground before climbing onto another wall, where it calms down after shooting more electricity, allowing Mario to continue. Once all the globes have been hit again, Mario must start attacking Mechawiggler in rapid succession yet again, eventually defeating it.
Once defeated, Mechawiggler, covered in electricity, shrieks one more time, before exploding from tail to head, releasing a Multi Moon. After defeat, a piece of Mechawiggler crashes in Mayor Pauline Commemorative Park and can be Ground Pounded to collect a Power Moon.
In the rematch in Peach's Castle, Mechawiggler has more segments and an extra head. This allows it to split in two during its charging attack, with which it starts the battle. Another change during the rematch is that Mechawiggler launches pink electric spheres that split into multiple bursts. The battle is otherwise the same. When Mechawiggler is defeated again, it will explode, releasing the Multi Moon.
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