Spiny Desert, as the name implies, is a desert-based board in Mario Party 3. It is not inhabited by Spinys, but Pokeys and a Chain Chomp. The board is divided into two sections: one half day, and the other (smaller) half night (this has nothing to do with the day and night system from Horror Land, or Mario Party 6's boards). The constant challenge of this board is to get to the real Millennium Star, because there are two on the board, and one of them is always a mirage (a usual illusion in deserts). Happening Spaces are around sand pits on both sides of the board. Players who land on one on either side are caught by the pit (along with anyone else around it), and are transported to the sandpit on the other side. Action Time happens when players decide to take the path with 2 cacti on it. Players have to jump over both cacti to get to the other side of the path. If they hit the first cactus, they bounce in pain over to the sign with the cactus picture on the left side of the board. If they hit the second cactus (the one with the flowers on its head), they bounce in pain over to the sign with the cactus picture on the right side of the board.
In Story Mode, the human player goes up against 3 opponents and battles here to get the Strength Star Stamp.