Something that Mojang should add in a future update (1.13 1.14?) is an underwater/coral reef biome. Not only should there be visible fish(which you would be able to kill, but that would be harder as you would have to be underwater a long time to kill fish) but there should be sharks these would be hostile mobs and when you kill them they drop fins?, teeth?, something. These sharks would also be able to destroy your boat as you are boating. Maybe a shark boss too(megaladon?, great white?).

The mob opportunities are endless, including octopi, starfish, whatever; on another note, the biome: Coral reef. This would be a couple of chunks of coral(new block; maybe like a cactus?), seaweed(slows you down) and other underwater features.

With all of these underwater things, you'd need an apparatus to go underwater for prolonged times. I'm thinking a specially made helmet that not only lets you stay under for longer than traditional enchantments but also gives you better vision than traditional enchantments. And perhaps there could be flippers too(kill a seal or shark? The deal could be in the same biome as the polar bear).

There are so many avenues for underwater exploration and mobs; I think that Mojang should seriously consider adding an underwater update.

Thanks!🦀🦑🐙🐬🐟🐡🐠🦐🦈🐳🐋

Edit: As I was thinking about it more I refined some of my earlier statements. Here they are in the form of an "update".

-added Coral Reef biome •added seaweed which acts like soul sand when walked through. Can be harvested with shears. Can be planted underwater on sand. If planted in sand above water it will shrivel up and die, giving you sticks. •added coral which acts like a cactus when you walk into it. Can be mined with an axe or hand(coral is hard right?) and gives you a coral block. Is in different colors and mainly for decoration. • new mob: octopus. Found in coral reefs these are neutral mobs that like slime blocks if you walk into them; you bounce off( or you get stuck idk) when killed gives you ink (or sticky blocks?)

-new mob: shark • hostile mob which can destroy your boat if you are boating in the ocean. When killed sometimes gives you a fin

-new mob: seal • found in tundras near oceans. Neutral mob which makes cool sound. When killed sometimes gives you a fin

-new boss mob: megaladon(great white?) • found near coral reefs(shark temple?) • surrounded by normal sharks and very powerful • can swallow you and spit you out a distance (like Tahm Kench if you play league of legends) • when killed gives you lots of xp and a shark skull(maybe more idk) kind of like ended dragon

-new item: flippers • can be crafted by 2 fins and be on feet as boots • allows you to walk through seaweed with no slowing effects and go faster through the water

-new item: water helmet(bad name idk) • crafted from . . . ?? Glass? Diamonds? • lets you stay underwater for ?? 10 min?

If you have any ideas let me know!! Enjoy!