3. Hydro Armour
Bear with me.
In the Futurama episode “The Deep South“, the crew are pulled deep under the sea in the Planet Express ship. Professor Farnsworth exclaims, “Good lord! That’s over 5000 atmospheres of pressure!” When Fry asks how many atmospheres the ship can withstand, Farnsworth replies, “It was built for space travel, so I’d say anywhere between zero and one”.
This is the essence of why Tony Stark requires the bulky, heavy Deep Sea or “Hydro” armour. We see him head into space quite frequently; most recently in The Avengers, of course, and that was without the aid of any kind of specialised space suit. And, as Farnsworth helpfully points out, heading deep into the sea requires completely different technology, if we’re going to be in any way scientific about this. When one of your greatest allies is the King of Atlantis, you require these kinds of things.
