I don't come across many zilean players who aren't me, let alone ones who play it in the fashion that I deem "Correct".
I believe Zilean should be played as a super-strength nuker, by stacking AP, Cooldown reduction and a bit of HP and Mana.
A Guide To Zilean's Abilities
Look, i don't remember the exact values of each rank of Zilean's abilities, nor do I care, but I do know how to use these abilities to their full extent.
General: Deals Huge Damage to Targets Near the enemy you hit with this spell after 4 seconds.
Great guide. Lots of good tips for those thinking of taking the plunge. I would offer a word of caution though for those who may think after reading it that Zilean is somehow a caster carry that can put out insane amounts of damage and terrorize the battlefield. By going AP, you WILL do decent damage but you should still consider yourself support and should always be mindful of where your allies are in order to slow a fleeing enemy, ult a dying ally [if he isn't surrounded and it won't be a waste], or speed someone up that has overextended themselves. I have NEVER seen a Zilean carry a team before. He just isn't built for it. That doesn't mean that you have to be a waste of space though and I think this guide makes you far more useful than 90% of the Zileans I've run across.
One thing I would note: I'm pretty sure that you don't have to use two minions for a double bomb, you can just put both on one minion, placing the second detonates the first, killing him and thus setting off the second. Great for making people wonder why they just lost half their hp when you didn't even put a bomb on them.
Also, most players (at least at my elo bracket) don't seem to notice bombs on minions anywhere near as often as they do bombs on themselves or friendly champs.
Malphite is a great choice for timebombing, just before he initiates with his ult stick one on him- you're guaranteed to hit everyone he does. Rammus, Amumu, Blitz, and other initiators are also great for proxy timebombs.
Also, might want to add the standard Zilean combo- timewarp timebomb rewind timebomb.
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