As Terran
Make:
Marine
CycloneMissile TurretTurrets remove the easy worker angle; Cyclones punish greed.
Open in the counter tool with Oracle tagged ->As Protoss
Make:
Stalker
PhoenixShield BatteryBlink and Batteries keep Oracles from snowballing.
Open in the counter tool with Oracle tagged ->As Zerg
Make:
QueenSpore Crawler
HydraliskQueens in pairs turn Oracle dives into bad trades.
Open in the counter tool with Oracle tagged ->
Zealot
Adept
Sentry
Immortal
Observer
Warp Prism
Colossus
Disruptor
High Templar