Finally managed to get into Tremulous really good over the last couple weeks. (Tried a few times, but I was turned away by the multitude of total dicks that plague its playerbase.)
The detail of its maps inspired me to try to imitate it. So I made a nice little hallway and spent some time trying to make it look nice. Dunno if I'll turn that into an actual map or not, but it's fun.
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EDIT: