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Detectors are units, structures, or abilities capable of revealing cloaked or burrowed units. Note: You can still deal damage to these units through area of effect abilities like psionic storm, or by means of splash damage attacks.

Terran Detectors

• Scanner Sweep (upgrade your command center to orbital command to gain this ability)
• Missile turrets
• Ravens
• Ghosts (EMP Round ability, temporarily disables cloaking)

Protoss Detectors

• Photon cannons
• Observers

Zerg Detectors

• Overseers (overlord unit upgrade)
• Spore crawlers
• Infestors (Fungal growth ability, temporarily disables cloaking)