For me, the most annoying ones are immorush/speedbow and anything with shard of sacrifice. Any retard can make an immorush that does well; I remember having one that went 60-0 before it lost a game :p Speedbows, while in theory should have a lot of variation, in practice don't; there will be maybe 2-3 cards that vary, and the rest are completely predictable. There will be the black holes, the graboids, one each of all of the 4-5 cost creatures like lava destroyer, abyss crawler, gargoyle, phase spider, etc. And shard of sacrifice annoys me because it takes forever to wait out twelve of them :p
Ghostmare is kind of annoying, but there are two pretty good counters to it in the form of sanctuary and time quanta to play ghosts.
Firestall isn't really that good, and I usually beat it when it comes up in the arena. I still don't know why people rant about this one.
Oraclebow: I think is really fun to play against. Many of my most enjoyable games were epic 30-40 turn games against oraclebows. These games sometimes take even longer than SoSa games, but at least I'm having fun because stuff is happening, rather than me just pressing spacebar against sosacs until they run out.
Immorush: I already mentioned this one, and voted for it (though I'd have voted for speedbow if it were on the list instead)
Poison Stall: This one bugs me, but after putting two purify in my arena deck, things have gotten better
Monoaether: Never had a problem with this one. Dimshields bend over to PC, especially pulverizer or even butterfly effect, and phase dragons bend over to gravity shield; if you have those two cards in play, you can beat nearly all monoaether decks. The ones with elite immortal are actually harder to beat because they're faster and get around gravity shield :p
Shard of Sacrifice: Ugh. Most overpowered card in the game right now. If you can control the game, you can just wait them out, but often they win via poison, and that's harder to counter, as you need either purify or massive amounts of healing.
