The horde spider is a creature native to Tor when it was hospitable.
Living in the tundra, horde spiders were hive creatures that hunted in groups. They sent out scouts who called for assistance when they found food. To signal the others they rubbed their hind legs together to make a chirping sound. When reinforcements came they would mob prey the size of a Yellow Snake. The Tandu learned how to mimic the call of the horde spider, and used it in times of dangerous infestations when scouts went to track the spiders, making the call midway between several nests so the spiders would arise and wipe each other out.
- Endless Space (2013)