Space Swap Hex
From the Super Mario Wiki
The Space Swap Hex is a type of Hex in Mario Party DS. The player who possesses it can choose to place it on any Blue Space or Red Space within five spaces from their current location. Then, if an opponent lands on it, they swap places with the one who placed it. If the player who threw it lands on it, the hex will be canceled out, but they will receive 5 coins. The player can get this hex by stealing it using the Snag Bag or get it in the Hex Area. Oddly, computer players never uses this Hex similar to how they never use Warp Dice Blocks.