This is an extension of Benefits of Amphibious Items? and covers the benefits of the Amphibious Enchantment for people.
If someone swallows a Snapper (as in the monster, see the linked question above) whole (no easy feat and its jaws must be held closed by a Rubberized band besides), crushes it with their bare hands or feet, or crushes/smothers it by lying on top of it, they will gain the Amphibious Enchantment. (Ditto if they use a spear tipped with a head made of their own bone; if you are the weapon, killing a monster with said weapon gets you its Enchantment.)
Such individuals can breathe air and water with equal ease, and their motion in water is significantly less hampered-like any Amphibious items, Amphibious people have the same drag moving in water as they do in air. However, in water they don't sink like they are in air; they can swim like a normal person and float like a whale or manatee does. They also have thermoregulatory/cold protection abilities equivalent to a dolphin's.
Someone who kills or eats twelve Snappers, however, becomes a Skyswimmer. Skyswimmers can swim or float in air like it's water (and vice versa), and standing on the seafloor is like standing on a valley on land to them, while standing in a deep-sea trench is like standing in a really, really deep mine on land (minus the incredible heat).
In other words, my question is How Useful Would The Amphibiousness Enchantment Be For People?
Specifications For Best Answer:
All the other questions of this kind just considered humans (AKA regular people), but all things considered, answers to this question should really consider the benefits of Amphibiousness for merpeople as well. By merpeople, I mean the standard version of the half-fish, half-human fantasy staple.
The best question will also account for:
a. the benefits of being able to be submerged indefinitely without drowning, having your skin fall apart, or getting wrinkly
b. the benefits of being able to not only float where you are in water (again, like a whale or manatee), but being able to swim and move in water with the same resistance as you'd get if you were moving in air
c. the benefits of being a Skyswimmer (being able to swim or float in air as if it's water, not to mention better take water pressure, etc.)
- Finally, the best answer will account for whether the Amphibious Enchantment will make humans and merpeople more equal or will just leave merpeople OP.