Water isn't really dangerous in the game...so i think it should affect your armor....iron gold and diamond armor...rust..you have to take your armor off before going into a lake river or a puddle...diamond gold and iron armor weigh you down so you dround...leather doesn't. i also think there should be scuba suits so you could kill octopus and other sea creatures you will have to come out such as sharks...squids...sea turtles..sea horse w/e you want. My suggestion is not to be taken in to consideration in short notice i am very patient..
thats good then ! lol no rusting for them just huge weights that drag you to the bottom of the ocean and make you slowly dround to a fatal death...