I got dealt Nasus twice today. The second time, our Sivir fucked off in the first minute. The other guys were already all "4v5 gg", but I went "more glory for us!"
We won both times. Tanky AP Nasus is rude as hell. (Evil Tome, Merc Treads, Abyssal Scepter, Haunting Guise, Frozen Heart.) Spirit Flame as many people as you can, slow down the squishiest one with Wither so he takes max damage. The Damage Dealt graphs were silly, I ended up with about twice as much as anyone else. A lot of that was minions, but the first match I did more than the enemy Annie and Tristana put together despite my beefy build.
Then I got randomed into my first Warwick game ever (yay free week), thought about asking for a trade with our Urgot, went "challenge accepted" instead, did super well, and won. Daaaaang.
Yeah I'm liking this mode.