Mosqurito

Drain are bee-like viruses from Mega Man Battle Network game. This virus hovers up and down a column of panels. When it ends up in the same row as the player, after a small period of time it dashes forward. If it hits the palyer, it latches onto them and incapacitates them, syphoning a set amount of their HP and recovers its own by the same amount. Stronger variants move faster and syphon more HP.

Drain1
Drain1 are red colored.

Drain2
Drain2 are blue colored.

Drain3
Drain3 are yellow colored.