Area Denial
One major ability Overwatch defense heroes usually have is being able to cut off enemies from entering a certain point on the map. Mei is the only hero that can block choke points with a physical ice wall that can also be extremely useful during other situations, if not being used to troll other players trying to leave the span. Similarly, a new defense hero could have some sort of skill to create a physical gap between critical choke points. This could be done through methods like creating barricades, walls, or chasms.
Moreover, this ability could also punish foes who try to go through it. This Overwatch hero could have a skill that can deploy multiple beacons on the ground which could then form some type of electrical gate(s) if they are within range of each other. Enemies will not be able to pass through this wall and will even get electrocuted if they attempt to do so.
