Zilean
All in Good Time
Lane harassment and consistent damage output.
Sorcery
Empowered abilities and resource manipulation
Summon AeryYour attacks and abilities send Aery to a target, damaging enemies or shielding allies.
Manaflow BandHitting an enemy champion with an ability permanently increases your maximum mana by 25, up to 250 mana.
After reaching 250 bonus mana, restore 1% of your missing mana every 5 seconds.
TranscendenceGain bonuses upon reaching the following levels:
Level 5: +5Ability Haste
Level 8: +5Ability Haste
Level 11: On Champion takedown, reduce the remaining cooldown of basic abilities by 20%.
ScorchYour first damaging ability hit every 10s burns champions.
Inspiration
Creative tools and rule bending
Cosmic Insight+
18 Summoner Spell Haste
+10 Item Haste
Magical FootwearYou get free boots at 12 min but you cannot buy boots before then. Each
takedown you get makes your boots come 45s sooner.
Adaptive Force
+9
Adaptive Force Adaptive Force
+9
Adaptive Force 
Health Scaling
+10-180 Health (based on level)
Why Summon Aery
Aery on Zilean allows you to proc the offensive damage with your bombs for more kill pressure as well as the shield on teammate when casting [E] on them.
Why Manaflow Band
Zilean's high mana cost abilities and wanting to spam them can make it difficult to keep up early lane pressure. Manaflow Band helps you overcome that issue with some mana sustain.
Why Transcendence
Transcendence helps you get to that 40% CDR sooner with just an item or two for mid game teamfight utility.
Why Scorch
Scorch's early game damage pressure pairs well with the high base damage of Zilean's [Q]. A few successful bombs in the laning phase can lead to an easy kill.
WhyCosmic Insight
Cosmic Insight is an all-around fantastic rune choice for Zilean as he can greatly make us of every stat.
WhyMagical Footwear
The free boots from Magical Footwear let you hit your mid-game item power-spikes just a bit quicker thanks to the high gold value.
I’ve Seen Their Death
Lane harassment and consistent damage output.
Sorcery
Empowered abilities and resource manipulation
- Summon Aery
Your attacks and abilities send Aery to a target, damaging enemies or shielding allies.
- Manaflow Band
Hitting an enemy champion with an ability permanently increases your maximum mana by 25, up to 250 mana.
After reaching 250 bonus mana, restore 1% of your missing mana every 5 seconds. - Transcendence
Gain bonuses upon reaching the following levels:
Level 5: +5Ability Haste
Level 8: +5Ability Haste
Level 11: On Champion takedown, reduce the remaining cooldown of basic abilities by 20%. 
Gathering StormGain increasing amounts of AD or AP,
adaptive over the course of the game.
Inspiration
Creative tools and rule bending
Jack Of All TradesFor each different stat gained from items, gain one Jack stack. Each stack grants you
1 Ability Haste .
Gain bonusAdaptive Force at 5 and 10 stacks.- Cosmic Insight
+
18 Summoner Spell Haste
+10 Item Haste
Adaptive Force
+9
Adaptive Force Adaptive Force
+9
Adaptive Force Health Scaling
+10-180 Health (based on level)
Why Summon Aery
Summon Aery is a great offensive as well as defensive tool on Zilean as casting [E] on a friendly target will grant them the shield.
Why Manaflow Band
Zilean is a champion who relies heavily on casting his ability often, sometimes leaving you out of mana during important fights. Manaflow Band helps you to regen that mana when paired with ROA.
Why Transcendence
Transcendence allows you to build an early ROA while still hitting that important mid game CDR cap.
Why Gathering Storm
Gathering Storm is a fantastic rune on Zilean as it allows you ro safely scale into a deadly late game carry with high bomb potential while still retaining your teamfight utility.
WhyJack Of All Trades
Minion Dematerialzer plays a key role in being able to keep the lane pressure/wave clear up so you're able to leave lane and find ganks or fights with your jungler. The bonus damage to minions allows you to clear waves in 2 bombs without stragglers being left behind to auto attack.
WhyCosmic Insight
Zilean's strongest stat is cooldown reduction as it allows him to get more of his high base-damage [Q] off as well as empoewring/slowing targets with [E].