To unlock this achievement you must first complete a mission in the fallen ghosts DLC, till you get a skill point. Then open you skills window and spend 1 point on the flash drone (this is under the fallen ghosts skill tab). Next equip the flash drone in your load out. Now use your drone by pressing
on the D-pad, then flash yourself by clicking
. Now you should have the achievement.
NOTE: this unlocked without buying the DLC before launch for some players do to a glitch, that is now fixed.