Unnamed Gamma Quadrant explorers who followed a ship through the wormhole in 2369 and took the forms of the crew's imaginings, including Rumpelstiltskin and the baseball player Buck Bokai, to study human imagination.
This species has no known name or true appearance. In the episode If Wishes Were Horses, its representatives arrive at Deep Space 9 unnoticed and begin appearing as figures drawn from the thoughts of the people aboard.
Miles O'Brien's bedtime story produces Rumpelstiltskin, Benjamin Sisko's holosuite hero Buck Bokai walks the Promenade, and Julian Bashir is confronted by an adoring copy of Jadzia Dax. Other fantasies appear across the station, and the crew then imagine a subspace rupture into being that seems about to destroy the system.
Once Sisko realises the danger exists only because they believe in it, the rupture vanishes. The alien wearing Bokai's shape explains that his people are on a long mission of exploration and found imagination puzzling; he hints that they may return, and leaves Sisko a baseball.