Maybe Chase could be captured by a new villain in Adventure Bay. The other pups would then have to use their unique skills. For example, Skye could use her flying skills to scout the area where Chase is held. Marshall could use his strength to break down any barriers. They would work as a team, just like always, to rescue their friend.
It could be that Chase is under a spell that makes him act against the Paw Patrol. The pups would first have to figure out how to break the spell. Skye might search for a magical flower that is said to reverse such spells. Meanwhile, Marshall and Rubble keep Chase occupied so he doesn't cause too much trouble. Zuma and Rocky would work on the antidote. Eventually, they free Chase from the spell.
Chase might be lost in a mysterious forest that has suddenly appeared in Adventure Bay. The Paw Patrol pups would need to brave the unknown. Rubble could use his digging skills to create paths if needed. Rocky could figure out any mechanical puzzles or traps. They'd face challenges like strange creatures and magical barriers but would be determined to save Chase.