Armor of the Reef Warden (Patreon)

Armor (half plate or plate), very rare (requires attunement)

This armor is formed from living coral. While you're attuned to it, the armor magically opens and closes around you whenever you don or doff it, as if you were a welcome part of its ecosystem. As a result, doing so takes only an action, instead of multiple minutes. You also gain a swimming speed equal to your walking speed while wearing the armor, and you can walk normally on any surface while underwater (such as on a wall or ceiling).

A thriving community of various spectral fish swim around the armor while you wear it, which duck in and out of its many crevices. You can call upon these fish for a variety of benefits. Once a fish has been used in this way, that fish can't be used again until the next dawn.

Barracuda. When you take the Dash action, you can make a single weapon attack as part of the same action, as a spectral barracuda helps propel your attack. You have advantage on the attack roll if you're underwater.

Moray Eel. When you hit a creature with a melee weapon attack, you can cause a pair of eels to wrap around and grapple the target. The target must succeed on a DC 16 Strength saving throw or be grappled and restrained by the spectral eels for up to 1 minute. A grappled creature takes 1d8 force damage and can repeat the saving throw at the end of each of its turns, ending the effect on a success. If the target is underwater, it has disadvantage on the saving throw.

Pufferfish. When you're hit by a melee attack or are grappled by another creature, you can use your reaction to cause a spectral pufferfish to inflate itself between you and the other creature. That creature takes 3d4 force damage from the fish's sharp spines, and you're immediately moved up to 5 feet away from that creature. If you're underwater, you move up to 15 feet instead. This movement doesn't provoke opportunity attacks, and if you were grappled, you escape from it.

Surgeonfish. You can use a bonus action on your turn to create a swirling school of spectral fish around you. The fish remain until the start of your next turn and grant any creatures of your choice within 10 feet of you half cover for the duration. If you're underwater, the fish grant three-quarters cover instead.

You stand on the beach, looking out over the sea, and only its surface meets your eye. To you, it seems vast, but lifeless. Empty.

But just below there is so much more than you could imagine: variety and color and life in uncountable forms. To me, the ocean's embrace is not barren, but vibrant. Full. Alive.

I wish others could see as I do, and find value in what has brought me such entrancement. To find, truly, endless wonder.

Those that refuse, who make themselves a threat to this world, will still find me. Me, and my friends, wardens of that wonder.