I was just in a 25 minute battle with some Japanese guy. I managed to kill his Spiritomb and Mega Mawhile with a combo of paralysis hax and Proygon-Z getting a Download Boost, but then his Gastrodon murderized my Mega Garde with a Mirror Coat. Then I sent Porygon2 out, and these two stared each other down for a good 15 minutes. I had to stall with Thunder Wave and Thunderbolt until he ran out of PP for Mirror move (he burned through Counter first, then moved on to recover), but he eventually had to give up and gave me some Scalds which boosted Porygon2's Traced Storm Drain to +6, enabling me to get an OHKO Ice Beam off.
Fuck, I never have had such a funny battle.