Zilean generates 2 / 3.5 / 5 / 6 / 12 experience (does not count towards level up) every 5 seconds. Time in a Bottle is on cooldown when the game starts.
When the amount stored is enough to level up an allied champion and Zilean has been out of combat for the last 10 seconds, he can right-click the target ally to initiate a 1 second channel (if interrupted, Time in a Bottle goes on a reduced cooldown)
A successful channel levels up the target and grants Zilean the stored amount as experience of his own.
Time Warp cannot reduce enemy movement speed below 110, reducing non-linearly when going below 220 (to reach close to 110 depending on slow strength, the amount varying between 110 and 120 if the target didn't purchase Boots of Swiftness)
Time Warp non-linearly increases raw movement speed when above 415 (doing so again when above 490)
Active:Zilean places a protective time rune on the target ally champion or himself, lasting for 5 seconds. If the target takes fatal damage during that time, they are put in stasis for 2 seconds and then revived, regaining a set amount of health.