Super Bowser Dice Block
From the Super Mario Wiki
The Super Bowser Dice Block is a special Dice Block that appears in Mario Party 10. It is a large purple Dice Block with glowing pink dots on its faces, spiked golden trim around the edges and a red Bowser emblem replacing the dot on the one face.
The Super Bowser Dice Block only appears on the Chaos Castle board in Bowser Party mode. When Team Mario reaches the homestretch, Bowser will burst through the door, grow giant, and fuse his Bowser Dice Blocks into the Super Bowser Dice Block. It acts like a regular 1-to-6 Dice Block unless it lands on the Bowser mark; if this happens, Bowser instantly catches up to Team Mario, no matter how far away they are. Additionally, Bowser rolls the Super Bowser Dice Block after each member of Team Mario takes their turn, instead of waiting until all members roll.