Shocktoxin

Shocktoxin was created by an unrevealed US military contractor for use by S.H.I.E.L.D., who in turn issued them to members of the Secret Avengers team. Crafted into flechettes with a monofilament edge, Shocktoxin projectiles could slice through almost any armour, and shots that missed left little evidence as the compound dissolved in minutes if left in the open air.

A hit from a Shocktoxin flechette would allow the never toxin to do its work – and a single flechette can knock out a healthy bull for about six hours. Human test subjects reported experiencing truly horrifying nightmares while knocked out by the drug. It is not known what the bull experienced.