Sustained Deeps Mages Yo?

A lot of the mages out there specialize in going R and then KABOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOM Or in regard to one magician Tibbers!!!

But what about the mages who don't nuke the team down instantly? Which are those, do you think, and what is their validity in the current tanky/bruiser/zed mid meta?