Throughout the Dark Sector, numerous enemies assailed Hayden. This ranged from obvious human enemies, to the mechanized weapons that they use, and even include a number of the Infested. Normally they can be classed into 3 types.
Throughout the Dark Sector, soldiers in hazmat suits attempted to hinder his progress as they collected the infested. Usually, they ended up as cannon fodder for Hayden to experiment with his abilities.
War machines used by the Lasrian forces as they grew more desperate. They all have particular weaknesses that enable a skilled player to defeat them.
As would be expected, a number of the Infested are present thoughout the city. Later on, they are significantly more difficult to defeat than humans.
As would be expected, certain elite enemies will punctuate story at various opportunities. And often require the use of a number of Hayden's abilities.