I promised you a rock texture that fits with the dungeon tileset.
I didn't want to send it without testing it ingame first, and then one thing let to another.
I pm'ed you the testing folder (it has the texture and also all the assets for the tunnel and sounds).
you can see it in action here.
http://youtu.be/3xnRTOVsb6o
There is one asset thats not in the level I sent (its in the folder and defined in the lua), and not shown on the video, its just a wall prop that you can clip on to any dungeon wall.
its called sx_dungeon_rubble_wall, and will make the wall look collapsed, I thougt it would be nice to "cue" the player that the walls can be broken.
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this is yours, feel free to do what ever you want with this.
Skuggasveinn.