Magnet Mania (Mario vs. Donkey Kong: Minis March Again!)

Magnet Mania, also called Floor 3 (Floor 2 in the PAL version), is the third floor in Mario vs. Donkey Kong: Minis March Again!. This floor is largely based on the floor of the same name from Mario vs. Donkey Kong 2: March of the Minis, as they both revolve around the use of Magnets, as well as Conveyor Belts and Conveyor Switches. Pop-up Gates are also formally introduced here to the player, even though one appears in Sandstone Stroll in Room 2-SP. It is also the first floor in the game to feature Capture Kongs, Thwomps and Pokeys. After the player beats Donkey Kong on this floor, they unlock the Magnet Mania Construction Kit in the Construction Zone, which contains all elements featured on this floor.

The background appears to be a storage facility with pipes, stacks of multi-colored crates and mechanical hands carrying other crates. The soundtrack consists of variations of the underground theme from Super Mario Bros., which were also featured in the March of the Minis counterpart of the floor.

New elements
This floor contains tutorial levels that showcase Magnets, Conveyor Belts and Pop-up Gates. The player can access and play them by tapping on the "?" icon in the bottom right corner of this floor's level select screen.

{|align=left width=100% cellspacing=0 border=1 cellpadding=3 style="border-collapse:collapse; font-family:Arial;" !colspan=3 style="font-size:15px"|

Magnets
!rowspan=2|In-game description !align=center|North American version !align=center|PAL version
 * align=center|''Mini Mario can walk up magnet walls!
 * align=center|''Mini Mario can walk up magnet walls!

''When Mini Mario reaches the edge of the magnet, gravity returns to normal and he falls to the ground.
 * align=center|''Mini toys can walk up magnetic walls!

''When mini toys reach the edge of the magnet, gravity takes hold and they fall to the ground. !Tutorial overview !colspan=3 style="font-size:15px"|
 * colspan=2|The player has to simply activate the mini to let it walk up a Magnet that runs along the left wall and the ceiling. The mini will eventually reach the edge of the Magnet and drop on the ground, where it will walk some more to the Goal Door.

Conveyor Belts
!rowspan=2|In-game description !align=center|North American version !align=center|PAL version
 * align=center|''The conveyor belt carries Mini Mario along its path, forcing him to face in the direction of travel.
 * align=center|''The conveyor belt carries Mini Mario along its path, forcing him to face in the direction of travel.

''Press the conveyor switch to change direction.
 * align=center|''Mini toys are carried along the path of a conveyor belt and are forced to face in the direction of travel.

''Touch the conveyor switch to change the direction of all the conveyor belts in the level. !Tutorial overview !colspan=3 style="font-size:15px"|
 * colspan=2|Soon after activation, the mini will fall from a platform onto a Conveyor Belt that initially runs to the left, leading into a wall. The player needs to tap on a Conveyor Switch at the bottom to change the Conveyor Belt's direction and lead the mini to the Goal Door on the right.

Pop-up Gates
!rowspan=2|In-game description !align=center|North American version !align=center|PAL version
 * align=center|''Pop-up gates can be used to block Mini Mario, and force him to reverse direction.
 * align=center|''Pop-up gates can be used to block Mini Mario, and force him to reverse direction.

''Simply press the flashing button and the gate will pop up for a short time.
 * align=center|''Pop-up gates can be used to block mini toys, and force them to change direction.

''Simply touch the flashing button and the gate will pop up for a short time. !Tutorial overview
 * colspan=2|After activation, the mini will head towards a Split Pipe on the right. If the player does not activate the Pop-up Gate before the Split Pipe, the mini will be warped back to its initial position. If the Pop-up Gate is activated and the mini walks into it, it will change direction and head to the Goal Door on the left.
 * }

Plus Mode
In Plus Mode, this floor is subtitled Floor 3+ (Floor 2+ in the PAL version). This version adds Color Blocks and Fire Piranha Plants to the regular levels, as well as Magnet Rods, a new mechanic in the game. These elements become available in the Magnet Mania Construction Kit once the floor is beaten on Plus Mode.

Compared to its Normal Mode counterpart, the background appears to be gloomier and to lack any activity. The soundtrack is reused from Spooky Attic, the seventh floor of Mario vs. Donkey Kong 2: March of the Minis, and is a variation of the Spooky House soundtrack from Mario vs. Donkey Kong.