Mission Type: Main Mission
Mission Name: Where is Caja?
Mission Giver: Thialg
Mission Start: In 008 at SC Magalan Map
"Caja is a powerful mage and Elex expert. She's also the mother of my child. Maybe she knows a cure for my infection with the invaders' strange, dark substance."
💬 "Where's Dex? Where's my son?"
"Caja has moved on. She's following a troop of Morkon Bloodhounds. I should follow her trail."
Go find Caja in 
Talk to Caja to finish mission.
Check other Missions in ELEX II on ELEX 2 Missions.
To track the next target of a given Mission, go to LOG, select the Mission you are interested in and mark it with [F] Mark on the map. You will then see on the in-game map where you should go to continue the mission.