Marine phytoplankton, specifically armored dinoflagellates, that release toxins or cause mass fatalities to any mega-fauna or otherwise. When these dinoflagellates bloom, they are given the title of harmful algae bloom or HAB. Usually blooms are caused from eutrophication, which is the over fertilization of nutrients in the water (Nitrates and Phosphates). With this over fertilization plankton will bloom. When this happens, dinoflagellates that produce deathly toxins will concentrate in the water and cause mass hysteria among the local communities; killing birds, fish and even people. Not only do these armored killers give off a toxin, they lead to hypoxia and anoxia which is the process of oxygen depletion that leads to minimal amounts of dissolved oxygen and no oxygen, respectively. This leads to dead zones where no life can thrive, all because someone put too much nutrients in the water. So inevitably, humans cause their own demise by over fertilizing.