Zilean is one of the most underrated AP Mid, so much, most of the players still think about him as a Support, that's fake and M5 show it to the world in S2. Your Q E and R are simply the god of trolling your enemy, also your W grants a massive CDR, 10 secs less every 10 secs? WOW.
You can Run with your E all the map and never run out of mana if you do this build.

The Q is simply a great AoE damage, so great it can get you surprises, sometimes people go into Genius mode and stick to each other to share their pain (getting you a double kill maybe or even more).

Well that's why I choose Zilean as a great AP Mid.

• Hard to play against

• Everybody sees you as an old man that does nothing (FALSE you're a monster of damage dealing)

• Zilean is Fun to play

• Helps a lot in Team Fights, not only with the awesome R but also with the awesome E and brutal Q AoE damage

• He can destroy most of the ADC, by saving your own ADC

• Diving is Really Easy with R

• Easy to Snowball

• Easy to get kills with good use of E

Most of APC like to waste their runes on Mana regen (really who needs this at all?) or CDR (Blue + 1 Item 40% CDR, no need of that).

Well everyone has an opinion and I respect that but, you really need that runes?, I say no. With a Full AP runes you're going to have a great harass at early, and you wont need to buy items like Amplifying Tome or Doran's Ring, well, you can buy Doran if you're having a hard time at mid.

I think all this runes are self explanatory but ill explain them anyways.

• AP Runes (Glyphs, Seals, Greater Quints): more AP means more damage, it's that simple, you get it to have a better harass or even to kill if your opponent is bad enough to stay low HP on lane.

• MP(Magic Penetration) Runes (Marks): as more MP you have you're going to need less AP to deal more damage, no mage can go without MP, it's simply a waste of AP to have 500-800 AP if you have 0 MP.

• First of all you're a carry, so you need offensive tree.

• Second, you need summoner spells CDR, flash CDR and a bit of mana is simply a great help.

The Items are pretty easy to understand why they're there. But I will only explain the core cause all the other are merely situational items that can be replaced if needed.

This is the most important thing to understand when playing Zilean, your role is to not only deal AoE damage but also to help your teammates, slowing down an enemy or using an R or transform your friend into Usain Bolt to save him, there's a good way to help mates and a bad one.

Good One: You use your E and then double bomb so you have again E and can save another One.
Bad One: You spam double bomb, use the R on everyone not caring of his role and using E to save yourself full Hp.

Maybe the hardest part to do with Zilean, your main way to farm is pushing the lane, that's bad, but if you syncro your pushes with the ganks of the enemy jungler (OBVIOUSLY NOT GANKING YOU) you can farm a lot, after pushing the lane wait a bit or focus on double bombing the enemy AP Carry, it can be hard sometimes but it's great when you get used to farm with Zilean.

Well I have to thank you for reading the guide, voting, comenting, and even giving it a try or seeing mistakes in it.