Time Bomb and Ult are the only reasons Zilean is viable dummy

You shouldnt focus only on armor, get at least Greater Seal of Health, Enchanted Armor is not that great because you dont build too much armor/mr, Recovery is much better.

It is ridiculous to completely ignore that Zilean is strong for being annoying in lane with his Time Bombs, and yet you dont even level them up. Zeke's Herald is by no means a good item for a support, specially Zilean, if you think it works for you, try other items, it will be even better. And btw, you mention only a few items, like every game you build the exact thing and if you do it, Im sorry but you're losing a lot of potential.

You dont show how to effectively play on the support role, and if you want to introduce a new style of playing a champion (and your guide shows a COMPLETELY different style) you should explain MUCH more about what to do early, mid and late game and what to actually do with the champion. By reading this guide I still have no clue on how the hell this could possibly works, and most people dont have time/wont see a video, so it is important to also show it on the guide.

I suggest you to read other support guides to see how you can improve yours and see all the things you're missing (because it is a lot).

You disregard any form of laning pressure by not even bothering with ANY offense at all. With this setup your ADC is like 1v2.

Switch Seals to Greater Seal of Health and maybe consider naming Greater Mark of Hybrid Penetration as an offense alternative. Spellthief's Edge is still a great start option and you can swap it to Talisman later on if you want to. I disagree on Zeke's Herald being that essential - you can mention way more useful items like Mikael's Blessing. Sweeping Lens after building Sightstone!
Maxing E is suboptimal because the only thing increasing is the duration and in combat it's pretty useless (trades in lane) making Q and W more viable to max out first.
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