Chalco, a wanderer and transient, frequented Docking Bay 9372 on Coruscant, where he gathered information about individuals. In 25 ABY, he assisted Jedi Master Luke Skywalker as Skywalker searched for the renegade Jedi Daeshara'cor.
During the initial months of the Yuuzhan Vong War, Chalco observed the dissenting Twi'lek Jedi, Daeshara'cor, as she departed Coruscant aboard the Lucky Star II, headed towards Ord Mantell. Subsequently, Luke Skywalker located Chalco and persuaded him to help in tracking her down, because Daeshara'cor's quest for superweapons to employ against the Yuuzhan Vong posed a significant threat to the Force and the galaxy. Chalco disclosed his observation: the Jedi's departure on the Lucky Star II. Skywalker then deduced that her destination was Vortex, the current location of Qwi Xux, the designer of the Sun Crusher.
Chalco became Luke's companion and developed a close friendship with the young Jedi Knight Anakin Solo. The vagrant accompanied Skywalker and his allies to the library world of Garos IV. When Daeshara'cor captured Anakin, Chalco attempted a rescue, donning an ysalamir skin in an effort to nullify Daeshara'cor's Force abilities. Unbeknownst to Chalco, the ysalamir needed to be alive for its Force-negating effect to function. Consequently, the rogue Jedi easily overpowered him, redirecting his own blaster bolt, set to stun, into his knee. However, Chalco's weapon proved valuable, as Anakin utilized it as a telekinetic projectile to incapacitate Daeshara'cor. Anakin and Chalco then delivered Daeshara'cor to Master Skywalker.
Following the Battle of Garqi, Chalco agreed to collaborate with smuggler Mirax Terrik to transport bafforr trees to safer locations, after Jedi Knights Corran Horn, Ganner Rhysode and Jacen Solo discovered the lethal effect the trees had on the vonduun crab armor worn by the Yuuzhan Vong warriors.