[Emperor Pan I]

ÈMedics in StarCraft II currently have an area of effect Flare ability (50 Energy), which allows the player to see an area near the Medic. This Flare will not act as a detector, but is great for attaining vision of high ground to spot for the Siege Tank, allowing it to hit targets otherwise not target able. this will be great for Reapers to back door, or in team games for Stalkers to Blink to strategic positions.
However a 'spotter' will not be necessary to go from high to low ground, because a unit on high ground will be able to see ground levels below it.

Also The Colossus will be able to see on top of cliffs, allowing it to climb up without a 'spotter.