Mark & Execute - this mod for GTA 5 allows you to mark enemies or any other targets, and kill them with a single button press, as is done in the game Splinter Cell: Conviction and Blacklist.
HOW TO USE: - X key - marks targets. Aim at an enemy and press X to mark them. - E key - press to kill all marked targets. - You can hold down the X key so you can easily mark targets on the move.