after searching for it, you find the split-Regi temple!, you approach it's door and since you have all the three giants, it opens!. As you walked into the temple's ruins you see alot of panels on the floor, and decide to go for Regidrago!....as you light up the correct panels, you go and interact with the statue in the top of the room...and....Regidrago appears!

"Reggidrago......"