Cruisers were aquatic siege weapons armed with one laser cannon used by the Wookiees on Kashyyyk. Heavy Cruisers were upgraded versions with heavier armor and two laser cannons. Shortly after the Battle of Endor, the resistance fighter Shoran ordered four Heavy Cruisers belonging to his personal army in Tunnatutikan to go up a river on a scouting mission. He lost contact with them after they were captured by Trandoshan slavers. The New Republic members Han Solo and Chewbacca ventured to Kashyyyk to assist in its liberation and joined with Shoran to destroy three Imperial jammers.
During the battle to destroy the jammers, Chewbacca's army freed the four cruisers and used them to bombard a jammer on a small island.
Behind the scenes
Wookiee Cruisers and Heavy Cruisers were first mentioned in the strategy guide for the 2001 video game Star Wars: Galactic Battlegrounds. Four of them appeared in a Chewbacca campaign mission. An optional mission objective is to free them and use them against the Imperial jammer. The mission and thus the ships appeared in the game's 2002 expansion pack, Star Wars: Galactic Battlegrounds: Clone Campaigns.