So Im headed to my first major event next month, a WKO. Im just wondering what the top decks are nowadays so I can try to prepare to counter them.

Gobby
Tsarina
Johnny Storm
Professor X
perhaps SR Constantine to add insult to injury

rinse and repeat

There tends to be a fair amount of variety, but there are a few cards you can pretty much expect to see at least a couple times:

Black Widow - Tsarina
Green Goblin - Gobby
Human Torch - Johnny Storm
Storm - Most any of the AVX ones
Professor X - Recruiting Young Mutants
Jocasta - Patterned After Janet

Blue-Eyes White Dragon - Monstrous Dragon
Jinzo - Trap Destroyer
Ring of Magnetism - Action Attraction or Monster Attraction
Doomcalibur Knight - Fiendish Fighter

Most any D&D Dragon (for its breath weapon); probably Red Dragon (for its global)
Human Paladin - Apprentice Harper (for global), Master Lords Alliance, Lesser Emerald Enclave (for global and natural ability, both)
Prismatic Spray - Lesser Spell

Constantine - Hellblazer
Blue Beetle - Jamie Reyes (if your opponent is playing a Villain heavy team... and if they are, expect to also see stuff like Black Manta and Cheetah)


For Basic Actions, there are a lot of great ones. Do you need to deal some direct damage? Try Magic Missile or Powerbolt. Do you need to manipulate your dice bag or used pile? There is Resurrection's Global or Polymorph. Do you need get past your opponent's blockers? Imprisoned or the global on Relentless might work. Lots of others, too.

normalview has a great list - you'll see many of these on most of the top builds.

you can easily google and find what happened at worlds and watch the top matches - not sure that much has changed in the meta since then.

the blue-eyes rare global to KO your own Grundy is pretty rude.