Comes-in-the-night-kills-many is the translated name of an insectoid species from the Gamma Quadrant. They are around eight meters tall and possess eight limbs with two pronged claws on each. The species also has the ability to fire spikes from its body as projectiles to injure its prey. It has been theorized that they have some form of intelligence.
Taran'atar and other Jem'Hadar soldiers were once sent by the Dominion to exterminate the creatures which had been killing agricultural workers on a planet. They would burrow under their prey before pulling them underground to devour them. (DS9 novel: Abyss)
When he was sent to Deep Space 9 by Odo, Taran'atar created a hologram of the species from memory to fight in the holosuites. (DS9 - Mission Gamma novel: Twilight)