PSA: If Zilean is your support, don't waste his ult.
Zilean's ult is Chronoshift.
The long version: ACTIVE: Zilean places a protective time rune on the target ally champion or himself for 5 seconds. If the target takes fatal damage during that time, they are instead put in Stasis icon stasis for 2 seconds and are revived with a set amount of health.
The short version: While golden hour glasses are floating around you, you have a Guardian Angel.
Don't waste it. Don't use skills and items to heal yourself. Don't run away only to return to the fight and get yourself killed as soon as it ends. Just die. Let yourself get killed and you'll come back with more health.
If the enemy run's under tower and he ults you, dive that tower, get the kill, and let the chronoshift do its work when the tower takes you out.
Also, if your team's
is attacking the tower while there are no minions under it, it means he's planning on eating tower shots and using chronoshift on himself. Help him out, he doesn't have very good ad, but you do, vandalize the hell out of that tower while it's focused on him.