I Never Asked For This

Deus Ex: Human Revolution is set in a future where humans use augmentations to enhance themselves physically and mentally. Following an attack at Sarif Industries, where Adam Jensen is the head of security, he was thrown through a solid glass wall and then shot in the head. The attack would have killed him had it not been for the augmentations he received to save his life.

During his sixth month recovery, many of the abilities of his augmentations were switched off in order to not overload his brain and send him into shock. The remain inactive until Jensen has mentally healed and adapted to the augments, or purchased software known as Praxis Kits, which allow him to speed up the unlocking of new abilities via Praxis points.

Details of the augmentations and the abilities available to Jensen can be found here.

Currently, this Jensen is a stealth pacifist, who has augments which aid in stealth and KO-ing opponents, not killing them.