Blizzard surprisingly released the Overwatch's new hero, Sombra, on Public Test Realm a few days ago. As we all know, Sombra is a flanker who specializes on disabling enemy skills and first aid kits sneakily. However, she differs from other flankers who focus more on offensive direct attacks and damage dealing.
Machine Pistol. Sombra has a fully-automated pistol with 60 rounds, so try to not reload before you need to. The best way to make use of this is trying to get behind the enemies while invisible and fire them from there. You can teleport out if things won't go as planned.
Opportunist. Sombra can see the enemies with less than half health even through the walls. Make use of this passive ability to figure out when is the perfect time to engage. This is also best used to figure out which way to go if you're being chased or when chasing an enemy with low health.
Translocator. Set up your beacon in a safe place like near ally team or hidden safe spot. You can sneak and scout in the enemy area and teleport back once spotted but always be careful with once shot attacks such as Roadhog's hook and Hanzo's arrow. Sombra can also make use of the translocator for escapes or chase.
Thermoptic Camo. Thermoptic Camo is Sombra's ability to become invisible for a short period of time. While invisible, Sombra has additional speed. However, using abilities or taking damage will disable the invisibility so don't use it when enemies have a line of sight on you. Note that you can be spotted with Widowmaker's ultimate ability even if Sombra is under this skill.
Hack. Hacking is one of the core abilities of Sombra. She is can disable enemy abilities for few seconds. Though this won't make a big deal for hitter heroes like Soldier, this is a threat to other heroes that rely on their abilities for effectiveness. Sombra can use Hack to also disable the health packs so it is best in combo with the invisibility while chasing or trying to kill low health enemies. Keep reminded that you don't want to just hack stuff randomly since this has a long cooldown.
EMP. Finally, Sombra has an ultimate ability that disables all the enemy ultimate abilities in a large radius around her. This is devastating since this will also disable all enemy shields. To make use of the EMP effectively, use it when both yours and enemy team are in a close team fight so your team can achieve better momentum. This will also prevent them to use their escape abilities.
Sombra will be dispatched in Overwatch main client sometime next week. Blizzard confirmed Sombra as a new hero during BlizzCon2016. For more detailed information about Sombra abilities, visit this Reddit thread.