Watcher

Watcher (ウォッチャー) is a reconnaissance robot that passes by the screen and shoots two electric beams from his eyes when a enemy is in his front. It appears in groups of six in Elec Man's stage and Dr. Wily Stage 4.

Captain N: The Game Master
Watchers appeared in "Metroid Sweet Metroid" where they command by Dr. Wily which one of them grab Megaman.