Blizzard promised and they have announced that they will deliver on that very soon as Ana Amari will be the next character to join the character roster for Overwatch.
Ana is a battle-scarred veteran who supports her teammates from a distance using her unique, and highly-specialised, arsenal. Ana’s primary weapon is her Biotic Rifle, which fires long-range darts that can restore health to allies, or deal ongoing damage to her enemies. Her Biotic Grenade is perfect for close-quarter clashes; simultaneously healing teammates and injuring foes caught in its area-of-effect blast.
If the fight starts to get out of hand, Ana's sidearm can be used to knock her adversaries unconscious with a Sleep Dart. Her Ultimate Ability, Nano Boost, transforms friendly teammates into super soldiers, allowing them to temporarily move faster, deal more damage, and take less damage from enemies’ attacks.
To learn all you could possibly need to know about Ana, hit up the official Overwatch site for the details. Because it won't be long until she joins the fight.