As Terran
Make:
Siege Tank
Raven
MarauderDisable, kite, and let tanks do the heavy work.
Open in the counter tool with Thor tagged ->As Protoss
Make:
Immortal
Tempest
DisruptorImmortals trade up, while Tempests keep Thors walking.
Open in the counter tool with Thor tagged ->As Zerg
Make:
Viper
Brood Lord
RoachAbduct isolated Thors and avoid clumping air over them.
Open in the counter tool with Thor tagged ->
Marine
Reaper
Hellion
Hellbat
Widow Mine
Cyclone
Viking
Medivac