User blog comment:Megames1/Against the Meta- Xerath, and More!!/@comment-5557556-20121021133510/@comment-79.175.113.242-20121021234933

EDIT: @Megames1

Read the remake again, Renekton's spells don't spend fury, fury builds up and with more fury you unlock additional effects. If you use Q with 70 or more fury it will deal increased damage and when you use it again, it will deal the same effects.

I think that is the main Renekton's weakness, he goes in with full fury bar, spends it on one spell and then he needs to charge it again in order to perform additional effect again.