Zero Accessability

My first map for SC2.
It's a 3v3 melee map of manageable size, where accessability is very limited, to the point where it's zero at the start of the game.
Ramps to all main bases are blocked by rocks, meaning that early rushes are quite difficult to pull off.
Four high-ground expansions in the middle of the map are completely inaccessible to conventional ground units.
Two high-yield expansions on the sides have unblocked ramps, however, and are easy to grab but harder to keep.

Note: although the low ground is flooded, it does not have any pathing restrictions and works like any other map.