Hello, my name is Forresto, and I main zilean support with a 70% win rate as him. Some people think you are trolling when you pick him, but I guarantee that they are bronze. Within a few weeks of picking him up, my ELO jumped up 250 points. This is only my second guide, so I welcome any feedback.

Pros:
-High poke
-High mana sustain mid-late game
-zoom zoom(high speed)
-crazy aoe wave clear (dont do this too much as supp)
-Free Guardian Angel
-Some crazy champ synergies
-Global passive
-only needs a few items to be useful
-huge power burst post-6
-mid-game can have almost infinite mana
can slow/haste twice simultaneously

Cons:
-Hates bears
-Super squishy
-no hard cc
-gets focused a lot
-countered in lane by supports with spammy shields. (janna, karma, etc.)
-extremely mana hungry till you get some items

The best runes for most supports are: armor seals, armor marks, MR glyphs, and gold per 10 quints. The reason is that zilean has a high base damage already. He doesn't need to assasinate the adc, just put out a steady stream of poke against the enemy bot laners. Therefore, the resistances are more useful in making up for zileans natural squishiness. He doesn't need CDR runes, as he will easily achieve max cdr on his own, and he doesn't need mana regen runes, as with proper management he will not run out of mana. With this build, he will have enough max mana and regen to never run out. The gold quintessences are very important, because passive gold income is one of your primary sources as a support, and the 3 gold per 10 will give you a decent amount of bonus gold.

I recommend 4/0/26 masteries. The 4 will go into the cdr masteries, while the rest will go into masteries relating to gold generation, and mana sustain, plus more cdr. This is key for giving zilean early mana sustain, and allowing him the money to build the items he needs.

the optimal start is:
Spellthief's Edge
plus a green ward, 2 health pots, and the warding trinket.
the spellthiefs edge will be your main source of gold income in lane. Always remember that if you are building it, you need to harrass the enemy. It doubles the potential gold from the item.

If you prefer it is also possible to build the Ancient Coin on Zilean. This is less useful than the Spellthief's Edge however it can be a more reliable source of gold generation if you are in a lane where you are too afraid to harrass such as laning against a leona.


Whichever you choose, upgrade it on your first back, and buy a 1-2 more wards depending on your gold stockpile. never buy more than 2 wards at a time, it will only set you back on buying items. If you still have money left over, an extra Faerie Charm is always good to have. Anytime you go back, try to pick up a ward or 2, it is extremely important for your lane.


You should try not to go back again until you have at least 775 gold, or enough to afford your tear, and 1-2 more wards. Once you have this item you can afford to be a bit more aggressive with your spells, but be careful not to overdo it.


Next back get a Sightstone after this you never have to spend money on wards again.


The last core item to get is a Chalice of Harmony once you have this you will likely never run out of mana ever again unless you have a very long team fight, or you are running around putting out fires. Spam your abilities as much as you want, theyre practically free at this point :D


After this you face a number of choices in terms of itemization. You have 2 items to rush, and you can choose between them at will. Frost Queen's Claim or Athene's Unholy Grail are both valid choices for the next item. Either way, they both need to get built asap. The reason is simple: zilean thrives at max cooldown reduction, known as cdr. Build both of these items, and you will reach max cdr in combination with your masteries. You will also not exceed the max, making this extremely efficient. Choosing which one to build first depends on 3 things:
-do you have enough for Frost Queen's Claim already, but not enough for athenes
-do you need the active from Frost Queen's Claim
-would the extra cdr, ap, and increased mana sustain from upgrading Athene's Unholy Grail be more beneficial at the moment?

Personally I tend to rush Athene's Unholy Grail if possible for the extra cdr, but it is really a judgement call.

After these 2 items are completed, you have a number of items to consider. Do you finish your tear? Boots are cheap. Do you build the final situational item?

One thing is that the Sightstone upgrade can probably be saved for last. It only adds 1 ward, and you don't need the extra hp.

Buy the first boots sometime after Sightstone. You need the man from the tear and the wards from Sightstone asap.

Upgrade the boots to 2nd or 3rd tier after you have max cdr. The reason you don't need to build the boots asap is that when you need move speed, cdr is actually more valuable since it makes it easier to spam Time Warp

2nd Tier Boots Decision:


Boot Enchant:

This depends entirely on playstyle. My top choices are as follows:
Rylai's Crystal Scepter: Probably the best choice, adds some AP for damage, a bit of HP for survival, and a decent aoe slow on every bomb. Extremely useful for controlling the flow of battle.
Rabadon's Deathcap: Not really your job but if you want a bit more teamfight damage presence, this is a decent pick.
Zhonya's Hourglass: If someone is diving you hard this can give you a bit of leeway so that you don't have to waste an ult on yourself. An ult on yourself is an ult wasted.
Liandry's Torment: If the enemy team is super tanky this is a good choice. It synergizes well with your sustained aoe damage.
Twin Shadows: gives you some extra move speed and a good long range slowing active for chasing, or finding preventing ambushes.

At level 1 you generally want to put a point into Time Bomb the exception to this is if your team wants to invade, Time Warp is more useful to add cc.
at level 2, assuming you started bomb, you have to choose between Rewind and Time Warp. Personally I prefer Time Warp. You you simply dont have the mana to be double bombing this early, and if you do get into a full fight, hasting your adc/slowing an enemy will likely be more beneficial.
At level 3, put a second point into bomb, and at level 4 pick up whatever skill you didn't grab before.
After this, your top priorities in order are: Chronoshift, Time Bomb, Rewind, Time Warp

Leveling your ult increases the amount of health your allies revive with. If you are building a heavy ap zilean you could maybe get away with only 1 point in ult, since it scales heavily with ap, but that's not you. The more health they have, the more impact a revived teammate can have on a fight.

You need the damage from Time Bomb to stay relevant in fights, and to do huge poke.

Rewind reduces the cooldown on everything. the more often this is up, the more damage you do, the more often you can revive, and at max level, you can literally perform a nonstop Time Warp.

Time Warp is leveled last because leveling it only increases the duration, not the effect. Level 1 already has a significant duration only slightly shorter than the fiddlesticks fear. I have tried maxing it first, and ultimately you have much less impact on a game.

Heightened Learning:
Pretty self explanatory passive, everyone get's more experience as a global buff. Nothing tricky here, and not very noticeable. Play and ignore.


Time Bomb:
This is your primary damage spell. Place it on someone, and 4 seconds later it will explode. In low elo play, this ability can lead to some pretty funny kills as people flash away from bombs that are already on them, shield too early or kill their teammates by stepping too close.




Rewind:
Probably your defining ability. This will reduce all cooldowns by 10 seconds when used.
Initially, the cooldown of this skill is about 20 seconds, but it loses several seconds per skill point, and with max cdr, at max rank it has a crazy cooldown of 3.6 seconds.




This is your primary form of crowd control. When used it will either slow an opponent, or speed an ally by 55% for 2.5 seconds to 5 seconds depending on skill rank.
A very useful skill, it synergizes well with a number of champs who benefit from move speed, such as master yi, or nasus. Also good for chasing, or getting an ally out of a jam.




Chronoshift:
The best ability that has ever existed on any champ. Ever. Use this on yourself or an ally, and that person will revive when killed. Basically a free Guardian Angel The heal goes from 600-1100 based on the skill level. The cooldown is not reduced by skill level. The revival can happen within 7 seconds of use.

If your jungler starts blue, use your trinket to ward the red buff at 1:40.
In lane you have several different choices to make depending on the situation. your adc probably wants to farm, and so does theirs. On the other hand, 1 or both adcs may be more focused on getting kills. It is up to you to tailor your playstyle to your adcs needs.
Options:

-Deny farm:


-Build a tent in the bushes:


-Scare the support:


-Set up kills:


-Remember to ward:

Support zilean doesn't farm in the traditional sense, but there are things he can do to get gold. Of course, my build features a number of passive gold sources, but it is important to remember the harass gold from Spellthief's Edge and Bandit

Part of mastering zilean is learning how to get as much free harass as possible. Autoattacks, and bombs both count for this, and autoattacks actually give even more gold due to the Bandit mastery. Don't be overly aggresive. You cannot take hits.

Mid-late game you will mostly be teamfighting and securing objectives. Your job is to control the flow of fights, and set up objectives like towers and dragons. There are several important things to remember for this:

-Wards.


-Teamfights:


-Asessing Threats:


-Objectives:


-Wards Again: