In SFCI, you died against them the first time you fought. After undergoing Guthix's training, you became capable of learning Guthix's Gaze. During your second battle once you were revived, you learned to control it and defeated them.
Around the end of SFCII, they appeared when you and the C were fighting Zamorak, they appeared and helped you defeat them. At the time, they were more powerful than you because they were training in RuneScape Heaven. They brought Zamorak to his second form, but then at that form he was easily able to kill them.