GemCraft: Chasing Shadows "Grey Trees" puzzle

So you may have noticed the achivement "Grey Trees" "11331791" in the list. I haven't seen anybody explain this code or the related codes yet, so here's my explanation. Non-plot spoilers follow.

It turns out that the code has to be entered by clicking the four corners of the main map (these may be easier to see if you use your mouse wheel to zoom out). The digits correspond to the corners in the following way:

SW = 1
SE = 3
NW = 7
NE = 9
so the Grey Trees code is SW SW SE SE SW NW NE SW. There are actually more codes, the full list seems to be:
11111111 SW SW SW SW SW SW SW SW
33333333 SE SE SE SE SE SE SE SE
77777777 NW NW NW NW NW NW NW NW
99999999 NE NE NE NE NE NE NE NE
13371337 SW SE SE NW SW SE SE NW
11379197 SW SW SE NW NE SW NE NW
97713791 NE NW NW SW SE NW NE SW
77919713 NW NW NE SW NE NW SW SE
79797919 NW NE NW NE NW NE SW NE
77311973 NW NW SE SW SW NE NW SE
11799397 SW SW NW NE NE SE NE NW
11319773 SW SW SE SW NE NW NW SE
11331791 SW SW SE SE SW NW NE SW
Any of the first four clear any codes in effect (you only get a message if there was a code in effect). I'll let you discover what the rest do—some are just cosmetic, while others affect gameplay in minor ways.

Entry first conceived on 15 April 2014, 1:36 UTC, last modified on 15 April 2014, 2:03 UTC
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