Harpooning, as instructed to me by the wise Dominions Mod Elders, causes the same effect as nets - defense reduction and next round immobility :
http://forum.shrapnelgames.com/showt...ght=harpooning
And no, it doesn't require ranging to work underwater, which kinda sucks for another mod I'm working on.
When I tried to upload my 1.1MB zipped mod, it threw an error at me.