Humans joined the galactic community after discovering a Prothean data cache on Mars in 2148. Their devotion to understanding and adapting to modern warfare left the staid Council races stunned. Humanity's persistence and unflappable spirit has taken them further than anyone in the galaxy could have imagined. Master of nothing but proficient in everything, human sentinels are often relied upon to draw fire on the battlefield. Sentinels relish their opponents' look of surprise when they realize they were focusing on the wrong enemy all along.