An asteroid field was discovered in the Castilon system, in proximity to the planet called Castilon. During 34 ABY, pirates belonging to Kragan Gorr's gang launched an attack on a Darius G-class freighter located in sector six of this very asteroid field. This raid, however, took a turn for the worse when a massive Kowakian ape-lizard was unleashed aboard the starship, which then devoured a large portion of the pirate crew. Soon thereafter, Resistance operatives Poe Dameron and Kazuda Xiono, who were piloting through the asteroid field as part of an unscheduled training exercise, received the freighter's emergency transmission and decided to investigated. They, along with their astromech droids, namely BB-8 and CB-23, located and saved the only pirate survivor, Synara San, mistakenly believing her to be a member of the freighter's personnel, and transported her back to Castilon.
The Castilon asteroid field was initially showcased in the Star Wars Resistance episode "Signal from Sector Six" in 2018.