Arcitc Zerg Ravagers are advanced forms of Arcitc Zerg Roaches. Instead of freezing beams, they shoot with special blue plasma projectiles that can hurt like metal object.

Arctic Zerg Spotters just like original Zerg Spotters are capable of attacking a targets in opposite of regular Zerg Overseers that only provides more control and detects hidden enemies.

(Zerg Ravager and Zerg Spotter belongs to Blizzard)