A Phazon Leech is a small organism found in large numbers in Metroid Prime 3: Corruption that feeds on the bioenergy of dead or wounded creatures. They are often found in swarms. They are found on the G.F.S. Valhalla and within the Elysia Seed. They do not present a threat in any way, but a large swarm of them can deal adequate damage. Killing all of the Phazon Leeches within a Leviathan will earn Samus the "Exterminator" Friend Voucher.