As Terran
Make:
Marine
Viking
GhostKilling Overseers makes mines, Ghosts, and hidden movement more valuable.
Open in the counter tool with Overseer tagged ->As Protoss
Make:
Stalker
Phoenix
High TemplarRemove Overseers before DT, Oracle, or Observer plays matter.
Open in the counter tool with Overseer tagged ->As Zerg
Make:
Queen
Hydralisk
CorruptorPick off Overseers before Lurker or burrowed movement becomes the fight.
Open in the counter tool with Overseer tagged ->
Zergling
Baneling
Roach
Ravager
Lurker
Mutalisk
Overlord