Serpent Fly and Dragon Fly

Description

These giant, flying insects attack by striking with their tail stingers. Their attacks dispel any beneficial spells affecting their target.

Dwelling

Serpenty Fly is recruited in Serpent Fly Hive.

Upgrading

Can be upgraded to Dragon Fly for 20 gold per Serpent Fly.

Strategy

Being only a third-level creature (i.e., easy to acquire) with such great speed makes it excellent for rapid exploration (i.e., give a hero only Serpent Flies).  Even better for thus purpose after being upgraded.