OU Ladder: Crawdaunt, MHera, Manaphy, Vincune, Banded Kyurem-B, Screech Dugtrio cores, Banded Diggersby, Stored Power Clef
Suspect Ladder: The same as above + pokemon like Mew, Taunt Toxic Gliscor, Tauntwisp Talonflame, Gengar and Togekiss.
Some of these don't really break the current stall teams easily (Togekiss and Talonflame struggle with Zapdos, Gengar dislikes Pursuit stall, Diggersby has to predict, but gets worn down by Spikes and Toxic), but they definitely make the matchup a lot better. Especially on the suspect ladder pokemon like Togekiss are a lot more effective, not only because Zapdos is less common, but also because it is a lot easier to pressure Zapdos because stall lacks Magic Bounce.