The stairs lead to a hallway with spikes that rise out of the floor when Mario approaches them. Take each step with caution and the spikes will reveal themselves slowly. The next hallway features rotating and moving rows of flames. Navigate the first set either by running past them with Yoshi (this takes some expert timing) or by jumping over them. The second set has high and low flame columns. Mario can jump over the lower ones and then either roll or use Vivian to duck under the high ones.
In the following room there is a blue pile of bones, speak to it and an army of dry bones will appear and try to force Mario from the room. Hit them with the hammer to clear a path towards the blue one, who will be running away. Once Mario reaches him, an inescapable battle ensues. Focus the powerful attacks on the blue dry bones as he will resurrect his cohorts. Area attacks are good for disabling the other enemies for a time. You may want to put Mario in the back for this fight seeing as when all 5 enemies are attacking, they deal out a large amount of damage.
Grab the key, and enter the next area. There will be a question mark box with an ultra shroom and gold bobs being fired. Navigate the bullets and head down the steps to face a second round of cannon at the bottom.
The next area has three question mark boxes containing a P-Up D-Down P badge and a Jammin' Jelly. The next room has four doors on two levels. Always travel through the door with the lit torch in front of it, or Mario will be dumped into the room before the looping hall. After going through a number of torch lit doorways, Mario finally walks into the underground city. In the center of this courtyard there are two chain chomps blocking the bridges. Use art attack to quickly disperse of them, as their high defense and immunity to fire will protect them from most other assaults. In the center of the are there is a heart box and a save point. On the left and right sides, use Bobbery to blow up the stone chain chomps to reveal warp pipes leading to the background. Hit these switches to reveal paper boat panels. Before using these, travel to the right and through three halls until Mario meets up with Gloomtail.
Gloomtail: HP: 80 Attack: 8 Defense: 2
This enemy will bite, stomp, and breathe poison at Mario. When Gloomtail powers up, have Vivian on the team to pull Mario into the shadows and into safety. He has 70 HP, so the battle will last for awhile, but perform stylish moves for extra star power and Mario will do just fine.
After Gloomtail is defeated he coughs up a star key. Use Bobbery against the wall to the right of his head, to open up a secret area leading to an ultra shroom and jamming jelly. Return to the castle and use the paper boat panel to sail to the door.
On the first floor of the palace there are four doors. Enter the one on the right in the foreground and use Flurrie's breeze in the center of the room to find a chest with a key.
In the door behind this one, Mario can walk through the wall on the right side to find a switch. Collect this key as well. In the room on the left side towards the foreground, hit the block on the left three times, and the block on the right twice. In the room on the left side in the background, destroy the stone block that Mario can reach and then continue to the second floor, he cannot yet get the key in this room.
2nd Floor
In the room in the foreground on the right, hide in the shadows with Vivian to reveal a box and the key. In the background on the right, use Bobbery to blast through the wall and get the key. In the room on the left in the foreground you must defeat the bones in the order of their difficulty from easiest to most difficult. This is easy, because they are in order on the ground from left to right. In the room on the left in the background, destroy the stone blocks that Mario can reach and return to the first floor.
1st Floor
Go to the room in the background on the left side and destroy the remaining stone block, hit the switch and grab the key.
2nd Floor
Go to the room in the background on the left side, destroy the remaining stone block, hit the switch and grab the key.
3rd Floor
On the third floor, place the star key in the pedestal and columns with key holes will rise from the ground. Place the keys from the rooms below into each pedestal and a stairway will rise in the room to the right of the castle. Exit the castle and walk towards the door on the right and the Shadow Sirens and Professor Frankly will greet Mario.
Mario must battle the three villains once again. Doopliss has 40 HP, Marilyn has 40, and Beldam has 30. Marilyn, the great big large one, can do the most damage with her lightning strike and charged attacks. Beat her into the ground first. If Mario has enough star power to perform an art attack, this will take a significant amount of HP from the whole team. Near the end of the battle, Doopliss will mimic Mario which makes him more powerful, but easier to dodge. Once on of the team members fall, work on the other two with Mario's powerful hammer attacks.
After the battle, go through the door on the right in front of the castle and walk down the steps. Mario will be met by a few Dark Wizzerds. At the right side of the area, use Flurrie to blow away a section of the wall, enter the doorway and climb up the ramp. Then use Yoshi to reach the raised door. In the next area there is a red switch on the right that triggers a timed platform that comes out of the wall. In order to reach this platform in time, hold Koops shell attack in front of the switch and climb the steps with Mario.
On the other side of the steps there is a question mark box with a cape inside and a doorway. On the other side of the door, walk up the steps to the left and enter an area with two arrow boxes. Hit the box on the left but not the one on the right. Walk back to the right and use Yoshi to cross the next gap. Further to the right, fall down the pit and hit the blue switch with Mario's hammer. Hop on the block as it rises. Go to the right again, and hold Koops in spin mode in front of the small red arrow block. Drop down onto the large red block and release Koops and walk off to the right in the middle of the ascent. Use Yoshi to cross the gap and head through the door.
