Well if you don't mind using Graves yourself, but in a different way other than mindless AoE, then Discodoggy's "Rick Frostly" team is a pretty good counter.
Here are some videos where he uses them (one is vs Graves/MPD/FoA):https://youtu.be/u8jxtsTijHI?t=642https://youtu.be/_qoRzy3f9Zs?t=1407https://youtu.be/0EE2JxX5D90?t=537
General gist is
Start off with Kid, do some damage and haunt
Graves uses Grave destruction, then regular damage a round or two until you should use Consume corpse
Switch to Ghostpup, do some damage until Kid revives on backline, then do the group heal
From there you can repeat or just keep the Ghostpup in depending on how the battle is going.
Movesets and descriptions are here:http://pvppetbattles.com/daily-battle/june-18-2015/http://pvppetbattles.com/daily-battle/december-2-2015/http://pvppetbattles.com/daily-battle/december-5-2015/http://pvppetbattles.com/daily-battle/december-6-2015/http://pvppetbattles.com/daily-battle/march-5-2016/