What Keystone is Optimal on Xerath?
Like the title says, I've been a Xerath player for a pretty long time (not recently, but when I was forced to mid before dynamic queue, I tended to pick him most games).
Since the keystones were introduced, however, I have found a really hard time finding a keystone that feels good on him. The only 2 that are really even viable options are death fire touch and thunderlords decree.
DFT isn't optimal because, outside his e, he has no single target spells, drastically reducing the effectiveness of the keystone. In addition, his E is his only defense against people closing the gap, so throwing that out to try to optimally use a keystone doesn't really seem like a good idea.
Thunderlords is also incredibly unappealing. If xerath is using his range (his advantage and the reason to pick him) the most you can hit with is a W and a Q. That means that the only time Xerath is procing thunderlords is when someone is gap closing on him. Other than that, its pretty mediocre.
So I'll ask you guys, what do you think the better keystone to run on Xerath is? And is there a world where they introduce a keystone that actually works well with his kit?