You're playing against a team that consists of

-Kayle (dps, heal, 1 slow)
-Zilean (caster / support, 1 slow)
-Anivia (caster / support, 1 stun and slow)
-Tryndamere (melee dps, 1 slow, self-heal)
-Alistar (tank, heal, 1 knockup and displace)

How do you win? How soon do you decide to surrender? Has this happened before? Is it possible to kill someone?

Exec. Calling / Ignite, focus fire, disable Kayle/Zilean : Fiddlesticks/TF, Stun/burst AOE : Annie, fast computer so you don't lag from Anivia (Winter Map), actually you just need disables / CC. When they get Banshee's, you'll need Ashe / TF etc. to pop it. And they only have 2 carries, Anivie/Tryn, one is melee, other is slow/squishy, when Tryn goes in, Anivia will be behind about 2 secs, kill Tryn first then bird/egg.