King Olsef was the king of the Norvagen army during the Fire And Ice war and the Metal Ages. His son is Dev who is next in line to be a Norvagen king. He was tricked into hating the Draigar for killing the dragons by Xenoz. He was captured by Xenoz's Ice Vorgan and while in captivity he discovered that it had been Xenoz who was killing the dragons all along and his hatred for the Draigar ended. He was saved by Dev and Kyra during the final battle at Dragon Mountain. Olsef would then become good friends with Siddari, leader of the Draigar, often planning battles with him. During the Metal Ages, Olsef planned the attack on the Odaku invaders with Siddari. He even lead a fleet of Man-O-War down a river to the Ramparts Of Ryousan.
There are two Olsef figures, one known as the Norvagen Olsef, and the other called the Fyren Olsef. It is unknown whether they are the same character or different people. The Norvagen Olsef came in the Portal Of Fire set, while the Fyren Olsef came with the Fire Storm Fortress and Fire Ambush sets.