What is the ideal Keystone Mastery for "

When I think Disruptors, two come to mind immediately. and . Both seem to have great Synergy with Thunderlords, as they can set it off reliably, and it doesn't force any unnecessary actions out of them. But what about Deathfire Touch?

Taken straight out of the Dev blog, here is how Riot describes "Disruptors".

> We initially called this subclass ‘control mages’ but realized that could be expanded to the entire group (that and ‘Utility Mage’ wasn’t a very good Class name). Disruptors specialize in locking down opponents or, in some cases, entire battlefields by creating intense zones of threat that only foolish enemies would dare wade through. Although not as reliant on their friends as Enchanters, the fragile and immobile Disruptors greatly benefit from allied presence - both to deter incoming danger and to help capitalize on targets they’ve locked down.

Deathfire seems to fit well with both, as, if I'm not mistaken, Zyra's plants apply it, therefore allowing frequent resets. Anivia's ult, of course, does the same. Which is the superior Keystone in general situations?

Also, bonus question, who do you believe fits under the Subclass "Disruptor", besides the obvious two. ( and ).