My Pally deck runs two sunwalkers and two guardian of kings. Generally try to bait those kinds of removals with those guys.
Although most mages don't seem to be running Polymorph in constructed right now. Aggro Mage and Freeze Mage are the two big Mage decks in the meta right now and neither runs polymorph.
The trick is actually against Druids running Keeper of the Grove. I have to try and put out some vunerable minions to bait those guys.
There's a Mage secret deck that I've seen several times in the past few days, and that one runs two Polymorphs. As much as people like to shit on Mage's secrets, they're pretty powerful and they have the tools to keep you from playing around them.
I tried to build an Ancient Warrior Watcher deck, along the lines of Handlock but using Rampage and two Spellbreakers. It still needs work to win games against the netdecks, but I think the idea has some promise. The problem I have is finding a good finishing combo that you can fish for, like Miracle Rogue or Handlock or Wombo Combo Shaman. It's very good at forcing my opponent to throw all their resources at it, but once they have, I have nothing left to finish the job.
Earlier in this thread, someone had one with Bloodsail Raiders. With an Arcanite Reaper in hand, you drop a Bloodsail, give it Charge, and Faceless for a total of 23 damage.. but that's 15 mana and requires 4 cards, 2 turns and an opponent who doesn't have an Ooze or Harrison Jones handy.
Leeroy + Inner Rage + Faceless is 16 damage for 9 mana and 3 cards, but they will both die to the whelps.
I think the best one may be Arcane Golem + Inner Rage + Rampage + Faceless is 18 damage for 10 mana. The upside here is the Golems will have 4 health. That makes them much harder to remove if their damage is not enough to finish the job.
It requires more cards, though, compared with Leeroy + Power Overwhelming + Faceless or Leeroy - double Shadowstep or Leeroy + Windfury + Rockbiter. So it requires a shell that's really good at card draw. Might need to go back to the old Control Warrior setup with the Goblin Auctioneers.