Is it possible to have as a neutral unit a mine? Just like neutral buildings?
That way you can place it in nat so players will need detection to expand there.
Zerg have an easier time expanding, protoss can do so with cannon, but not an optimal fast expa and terran have the most trouble waiting for either turrets, scan or firebats/siege tanks.
No they don't! If you go sprites>unit sprites>terran>special>vulture spider mine (with player on 12-neutral)then those mines will be visible for a short time at the begining but then they will burrow and become invisible whether you are terran or not, try it.