Underground Moon Caverns

The Underground Moon Caverns is a lava-filled cave complex in the Moon Kingdom in Super Mario Odyssey. It serves as Mario's final trial before reaching the Wedding Hall and confronting Bowser. Unlike the surface of the Moon Kingdom, this area has normal gravity. A variety of enemies are found throughout, all of which Mario can capture to help him get past the obstacles in the caverns. Madame Broode awaits Mario at the end.

By Ground Pound Jumping off of the head of the Sphynx near the entrance, then performing a series of Cap Dives and Wall Jumps, it is possible for Mario to reach the Wedding Hall without ever entering the Underground Moon Caverns.

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When Mario enters, he will fall a long distance before landing near two Bowser Statues. Capturing the one on the right and moving it reveals a Power Moon. Up ahead, he must drop down further onto a platform with two Parabones and capture one of them, then fly above the lava while dodging more Parabones, Lava Geysers, and Sherm bullets. Upon reaching land again, Mario will encounter more Lava Geysers and Parabones. There is a cage here with a Life-Up Heart in it; the cage can be destroyed by Sherm bullets. At the end of the path is a platform with a lone Sherm, a locked panel, and a caged spark pylon. The key to the locked panel is in a hole in the lava to the right, which can be reached with a captured Parabones. The cage around the spark pylon can be destroyed by Sherm bullets, allowing Mario to travel upward to the next section.

At the start of this section is a Ground-Pound Switch and a ? Block containing a heart. Hitting the switch causes a platform to start moving. Mario must ride the platform over the lava past some Hammer Bros. Mario can capture the Hammer Bros. and use their hammers to destroy the rock walls up ahead that would otherwise push Mario off the platform, though he can also simply get over them with Backward Somersaults or Triple Jumps. At the end of this path is another switch-activated moving platform which takes Mario past some Tropical Wigglers and three regional coins. When he gets to the end, he will find two torches; the right one contains a heart.

The following area has Mario capture a Banzai Bill and fly over the lava, with some regular Bullet Bills and a second Banzai Bill Cannon found on the way. Additionally, he can ride the Banzai Bill to the right of the bridge to find an alcove with a treasure chest containing a Power Moon. A spark pylon will take Mario back to the bridge. Two more Power Moons are found in the Banzai Bill section: one behind the first wall and another buried on top of the second Banzai Bill Cannon. There are also three regional coins next to the second Banzai Bill Cannon. Crossing this section successfully leads to a platform with a Moe-Eye and another switch on it. Hitting the switch temporarily spawns an invisible bridge that can only be seen through the Moe-Eye's shades. An small offshoot of this bridge has three regional coins above it. At the end of the bridge is a spark pylon that leads to the next section.

Mario will find a Chargin' Chuck surrounded by stone blocks, which are broken when the Chuck hits them. One of them contains a heart. Mario must capture the Chuck in order to get past the rolling boulders blocking his path. Up ahead is a narrow path with more boulders rolling on it, which can be destroyed by capturing another Chargin' Chuck. Behind the Chuck is a platform with three regional coins on it. Getting past the boulders leads to a spark pylon that takes Mario to an above platform where he must rematch Madame Broode. After defeating her, the exit is just ahead. The torch to the right of the exit contains a heart.