When I think Black Marsh, I think:
- navigable canols with boats and rafts sailed in real time by the player
- lots of underwater life and predators that attack your boat (spears please)
- very thick vegetation with a lot of hidden dangerous fauna, swarming insects and poisonous plants
- a generally high fantasy magical and dark atmosphere, even more alien than Morrowind's; high contrasts between the depressingly claustrophobic inner canols and the peacefully calm misty lakeview shores with fishing villages and their traders boats
- a lot of variety in settlements (very weird culture and architecture) for the different Argonian tribes and more types of subraces
For me Black Marsh would be the ultimate adventure for a TES setting and I really hope Bethesda has already chosen it for TES VI. I can't even start thinking of the jawdropping beauty they could pull off with the next generation of hardware.
http://i53.tinypic.com/xnb3g4.jpg
http://fc06.deviantart.net/fs70/f/2011/008/d/3/swamp_fever_by_andreewallin-d36oonx.jpg
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http://1.bp.blogspot.com/_mlrLA5e06PY/TLJCledXucI/AAAAAAAAM58/aKfPagouWnI/s1600/Manatee+Springs.jpg
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http://www.tothailand.com/wallpaper/krabi/krabi_swamp_forest.jpg
http://www.birdingreports.nl/kaaku-swamp.jpg
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