Chaos Castle

Chaos Castle is one of the five boards in Mario Party 10. It is set in Bowser's Castle which is surrounded by lava. The mid-boss fort is home to a Mechakoopa, while Bowser (and by extension, Dry Bowser) is confronted at his throne. Most of the board's gimmicks have to do with lava enemies.

Gameplay
Chaos Castle features three distinct sections. In the first section, players must advance along a stone and metal path over a sea of lava while avoiding Lava Bubbles and Charvaarghs. At certain points, the captain will have to jump over a gap in the path while avoiding jumping Lava Bubbles; being hit by one of the jumping fireballs will make the captain lose some Mini Stars. If the players land on an Unlucky Space, a Charvaargh will appear and steal five Mini Stars from the current captain. At the end of the path is the mid-boss fort, along with a tunnel that leads to the next section of the board.

The second section of the board has two splits in the path that lead up walls with Skewers as obstacles. If a Skewer hits the vehicle, it will drop to the bottom of the wall as the captain loses ten Mini Stars. After navigating through the walls, the players will arrive at a pair of massive double doors that lead to Bowser's throne room.

The final section of the board involves players approaching Bowser through a long, straight walkway over a large lava pool. Players must try to end their turns in the lowered sections of the path; if they are left on a space in the higher section (indicated by an orange aura around the vulnerable spaces), Bowser will spit a fireball at their vehicle, deducting half of the current captain's Mini Stars. When the players reach the end of the walkway, they will face off with Bowser in a final boss minigame.

Unlike other boards, Chaos Castle features the Yellow Toad locked away on the instead of Bowser; The player who frees him is rewarded with twenty Mini Stars.

Bowser Party Changes
Chaos Castle follows most of the usual Bowser Party rules; Team Mario must head for the Super Star at the end of the course, while Bowser tries to catch them and deplete their Hearts. However, there are a few specific gimmicks to make things more difficult for Team Mario.

In the first area, Lava Bubbles and Charvaarghs deplete half of the current captain's hearts if they get hit. There are also a few Lucky Heart Spaces to give Team Mario a chance to earn some extra Hearts.

The Skewers in the second area are replaced with Rocket Engines that halve the current captain's hearts if they land on the right space. However, they will not dislodge the vehicle from its spot, and not all of them can be active at once (4 will be active on the first wall, and 6 will be active on the second wall). Bowser chooses which Rocket Engines will be active when Team Mario arrives at the split in the path; by distributing the active engines, he can influence the opponents into taking a less advantageous path (which has fewer Dice Block and Heart Spaces, but also fewer Rocket Engines).

If Team Mario reaches the third and final area, that is, after the homestretch, a scene shows Bowser bursting into the room (putting him one space behind Team Mario no matter how far ahead they were before entering the throne room), growing giant, and fusing his dice into a single large die. This new die replaces one side with a Bowser icon; if Bowser rolls the icon, he will catch up to Team Mario no matter how far away they are. Bowser is also able to roll his die after each active team member's roll (instead of waiting until everyone rolls the die). As a trade-off, Bowser does not get a bonus from Bowser Jr. at the "Almost There" flag - on the other hand, he enters a permanent state of Anger, ensuring that Team Mario will have to endure his most difficult and damaging minigames if he catches them.

Despite the unique upgrades, Team Mario and Bowser's goals are still unchanged; the former must make a break for Bowser Jr. and the Super Star at the end of the course, while Bowser attempts to finish his enemies off with his minigames and Bowser Jr. spaces. If Bowser wins, he will revert to his normal size and celebrate his victory with Bowser Jr. and a Hammer Bro. If Team Mario wins, the four teammates will celebrate their victory, leaving Bowser (still in his giant size) stomping his foot in frustration wherever he was when the Super Star was claimed.

Trivia

 * Chaos Castle is the first Bowser-themed board since Mario Party 6's Infernal Tower to lack Bowser's name in the title.
 * In Bowser Party mode, Chaos Castle gives Bowser two unique attack animations in addition to the standard animations; one when they're climbing the walls in the second area, and another when he's giant in the final area.
 * Chaos Castle is the first, and currently only Bowser-themed board in the entire series to not be unlockable.