Maxing E first on Zil makes his utility kinda disgusting
Hopefully what I'm posting isn't "news", but yeah.
Putting a 99% slow on someone makes it so ridiculously easy to line up your bombs for a stun that it's practically unfair. There isn't a single juggernaut in the game that's not getting peeled off of your backline (okay, Garen is if he Q's out of the slow) if you use this combo on them.
With 40% CDR, you'll be ready for another combo by the time they're able to move at a normal speed again. I encourage you all to try this before asking for another Zilean buff. He's super strong at the moment.
passive is worse