Bob-omb Factory is one of the seven boards in Mario Party 9. The players ride in the Factory Walker, the starting vehicle in this board. The Gear Shifter and the King Bob-omb Bus can be purchased at the Museum. The mid-boss fought here through the boss fort is Whomp and the boss which is fought at the end of the factory is King Bob-omb.
The players start out in a room which contains lots of Event Spaces. When those spaces are triggered, the conveyor belt moves the players around in the room, possibly collecting Mini Stars along the way. Once they get to the end of the room, there are stairs which lead the players to the boss fort where a mid-boss (Whomp in Solo Mode) is fought. Once the battle is over, the players will then head through a pipe-like corridor. One of the gimmicks that happens through the factory is the Bob-ombs that fall on the vehicle when the players pass a Bob-omb sign. The Bob-omb explodes after their legged machine has passed 10 spaces making the captain lose half of their Mini Stars. The platforms move forward through the corridor. If the player is lucky enough, they might get Mini Stars along the way. In the background of the factory, it shows how Bob-ombs are made. Once the players reach the end, they fight a boss.
The characters ride an odd walking machine on this board. The vehicle available from the start is the Factory Walker. The Gear Shifter and the King Bob-omb Bus can be purchased from the Museum for 200 Party Points each.
In this Captain Event, the players leave their team vehicle and board carts that travel down a short path. The captain who landed on the Captain Event Space selects which path each player takes. Regardless of who rolled the dice, all players move simultaneously. Between the second and third spaces of the paths lie two sets of three Mini Stars which begin the event on the two leftmost paths, between the fifth and sixth spaces lie sets of five Mini Stars which begin in the two center paths, and after the final space lie sets of 10 Mini Stars which begin on the right. The second, third, fifth, sixth, and final spaces are Event Spaces, and landing on these causes all Mini Stars to shift one path to the left. This event is unfavorable to the rightmost player, since one event space will shift the stars, making the player miss them, and CPUs will always put the player here if they are the captain.
Whomp Boss Battle
The name of this minigame is Whomp Stomp. The players are on a rotating platform. Whomp is behind them. The players hit switches to rotate the platform by adding 0 or 1 to it and try to avoid being crushed by Whomp. If Whomp misses, he gets damaged by the other players who Ground Pound him on the back. If the players are unlucky enough, they will get hit and lose points. Once his meter is orange, then he will stomp on the switch that will make the switch add 2 or more.
King Bob-omb Boss Battle
The name of this minigame is Bombard King Bob-omb. The players are on a big steel square and King Bob-omb appears behind it. There are four different sizes of Bob-omb in front of him. The players must choose a size of Bob-omb to pick up and throw at the boss. The bigger the Bob-omb, the more points the player gets. If two players choose the same Bob-omb they will run into each other and not get the bomb. Once at orange health, King Bob-omb will throw bombs at players who run into each other, these bombs make players lose one point. In 2 player mode, he might pick up a Bob-omb and throw it at the player if he is below half health.
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