Biomass Carrier

When this creature is blocked, sacrifice Biomass Carrier and deal 4 damage to the creature that
blocked it. When this creature dies create 4 2/1
black mutant creature tokens called "Infection
Form" with "{t}, sacrifice this creature: return
target non mutant creature with mana cost less
than 4 from an enemies graveyard to the
battlefield under your control or creturn
target mutant creature with mana cost less
than 4 from your graveyard to the battlefield
under your control."