@emoriam

Hm, I think I will change the mastery for that as it looks better. And for the Mpen mark, I'm still finding my place between AP, Mpen and Armor. The reason why I took armor was so that I would survive that early skirmish at bot lane. Maybe poke > fighting, but I will experiment with the Mpen runes or even what Grurin suggested. Thanks for commenting though! I'll remove the image too. c:

@Grurin

Truthfully, I usually max my Q first, but most of the time, I max it at level 10 just for the security of the lower cooldown stun. Personally, I feel that maxing stun would encourage readers to not focus so much on killing, rather, providing CC and aiding the ADC in the fight. Perhaps I will change it to maxing Q first. Well about the Rylai's, I guess I pick it up when my team is ahead because I have more gold. I will add this to the guide though. Otherwise, I'd go for Athene's instead. And you should try Xerath support! Also, thanks so much!

I'll see you guys in the Summoner's Rift.

-thewaterz

Are you sure maxing the stun first is a good thing? I know, 18 second cd sucks but you have to fall hard on poking then. Arcanopulse lvl 1 does minimal damage on champion lvl >5-6. And is on 10 sec cd. I'd personally max Q or even W first and then turn to E.
Another thing is Rylai's Crystal Scepter. Slows just for 15% on Q and R. Your E stuns and W slows by up to 90%. Plus you have the active from Frost Queen's Claim. Is that 15% really worth it? It comes with lot of awesome hp, but I don't think it's worth the money.
And I would think about the runes, maybe changing armor seals for hp? Plus what emoriam says.

Overall I love the idea of Xerath support. I was thinking about giving it a try since the rework, but I didn't have time to. Good luck!

Summoner's Insight > Expanded Mind , Greater Mark of Hybrid Penetration (considering Spellthief's Edge)/ Greater Mark of Magic Penetration > Greater Mark of Armor

Your screenshot in the section "Ranked Play" is way too big and pixelated ...