Razen, the Edge of Time is a custom template champion in League of Legends.
Theoretical Item Build
My 3rd custom champion concept, another caster, this time with an emphasis on... something, I dunno. Couldn't think of a better passive, so I went with a boring stacking concept. Remember, as with all concepts, the concept itself is key, all numbers are subject to change.
PS: I thought that might as well give a second suggestion for an ult, but I personally like the 1st one. This one would work better on a caster with an emphasis on landing skillshots from multiple angles.