so, concept:
Spartan Isle

10x10 1v1 map
Players start top left and top right.
The top most landbridge is to be blocked by a wall of reclaimable rocks (that only give energy)
a majority of the metal is going to be on the bottom plain.
the white areas are water.
so, heightmap sketch:

and this is where the troubles begin.
I figured liberal use of the blurring tool would get rid of the sharp edges, which to an extent it did, whilst an outer blur on the entire island would create a gradient leading into the sea rather than a 90 degree drop off, but this still leaves the problem of blending two colour areas.

What photoshop tool is used to, for example, lasoo a black square and a white square and turn it into a grey ramp (moving from blackk to white)? my concept is based on flat areas connected by smooth ramps, so this is pretty much vital for any coninuation