You already told us, with obs and scourges.

True, but there are still some kinks to work out, in particular Science Vessels tend to screw it up epicly. And I'm still trying to find the Observer-to-tile ratio (The number of tiles between Observers) that gets the best accuracy without using up too many units. (Map Max sucks...) Not to mention, it's a lot harder to figure out where there isn't a Scourge than it would sound. (I do know how to do it, it just takes a little to long for my tastes right now. Or maybe my comp is slow?...)

Current system is best. The scanner sweep could be used to scout the enemy base. It's also limitless in how far you can use it.

Oh. I though your teleportation spell did have unlimited range. *facepalm*