Dreamy Sandoons are the Dream World equivalent of Sandoons that appear in Mario & Luigi: Dream Team, being the only Dreamy version of an enemy to debut in this game. Dreamy Sandoons have purple bodies and green antennas instead, unlike their Real World counterpart. In the field, Dreamy Sandoons occasionally stretch themselves vertically, making themselves impossible to jump over at full stretch, and contract shortly afterwards, repeating this pattern. Dreamy Sandoons move around at a slow pace and don't chase Mario or Dreamy Luigi upon sight, nor do they stretch or contract at a different rate around them, being one of the few enemies in the game who don't act differently around the Bros.
In battle, Dreamy Sandoons appear in large hordes of thirteen to twenty-four. They can attack by advancing towards Mario in vertical (from the player's point of view) yet sometimes crooked lines of up to six at a time. While doing this, the Dreamy Sandoons sink into or rise out of the sand, and Mario must jump over or on to them when they're close enough in order to avoid this.
A Dreamy Sandoon may also attack by sinking into the sand while advancing to spots around Mario, for it after a brief moment stick its head out of the sand by one of Mario's four sides, with up to three other Dreamy Sandoons doing the same from one of the unoccupied sides. One of the surrounding Dreamy Sandoons will be carrying a spiked ball on its head, and after they all quickly sink back into the sand and pop out again, the Dreamy Sandoon with the spiked ball will fling it at Mario, who must knock it back with his hammer to avoid taking damage.
If the Dreamy Sandoon with the spiked ball rotates clockwise before sinking back into the sand to pop out and throw, the Dreamy Sandoons will all move to the position of the Dreamy Sandoon that's next to it clockwise, the one with the ball throwing it from its new position. Likewise, if the Dreamy Sandoon with the ball rotates counterclockwise before sinking, the Dreamy Sandoons will all move to the position of the Dreamy Sandoon that's next to it counterclockwise, and the one with the ball with throw it from its new position.
The spiked ball attack will repeat in waves until all Dreamy Sandoons (or all but one Dreamy Sandoon) have had their turn to attack unless there is only one Dreamy Sandoon left, where it would perform that attack alone. The rising and sinking attack will repeat in waves until all Dreamy Sandoons (or all but four Dreamy Sandoons) have had their turn to attack.
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