Man clad in black

The crushed helmet poured down crimson blood, dyeing an inch deep puddle of rain water accumulated all-over the a foot high walled gardened garden.

All the knights remaining, 100 or so knights felt horror at the sight as they felt something boil inside of them. Their trained instincts abruptly heightened, but they understood that it wasn't going to remain the same for long, at most as long as their mana burned.

The mana reservoir differed from man to man, so they approximated their own strengths as they unknowingly entered to a state of adrenaline rush, where their blood shot up into their minds, making them feel a sense of fulfilling omnipotence that devoured the fears their hearts indefinitely bore.

That adrenaline rush was called "Survival Instinct."

It was an instinct that was inherited by every living being, indefinitely, but were only able to wield in the face of death.