Only battled against my friend so far, they turn out to be quite funny usually.
This one time I used Ice Fang on her Absol and it froze. The next round, I used Fire Fang for some reason and it of course melted since I used a fire-type move. It killed off my Mightyena.
One time in 2v2 battle I switced my Chatot (full HP) to Manectric (full HP) when against her Torterra (Oh noes, my birdie be in danger!). It used Earthquake.