SEA PICKLE

Most light sources go dark the moment water touches them. Sea pickle does not: placed underwater it keeps glowing, which makes it one of the few blocks that lights a reef or a flooded build without needing to be drained first. The Wandering Trader sells one for 2 emeralds.

It has no crafting recipe and no dye hidden inside it, so this is strictly a light-source purchase. In the world it clusters naturally in ocean and river environments, so unless the build sits on the coast already, buying it is usually cheaper than a dedicated expedition out to find some.

The Wandering Trader is the only seller, asking 2 emeralds for 1 sea pickle, with no buy-back offer at any price.

No profession villager stocks it. Ocean-sourced decoration like this sits outside the job system entirely, so the trader's row is the whole market for it.

He asks 2 emeralds each, and 51 of the other 75 come cheaper. Price is the easy part: he draws his stock from a shared pool, so catching one that happens to be carrying sea pickle is the real constraint.

The Wandering Trader asks 2 emeralds for a sea pickle. 8 of the 72 villagers that pay emeralds, emptied out:

2 compasses against 48 flint for the same 2 emeralds, 24 times the carrying, and the shortest wait is the Shepherd at 1.3 real minutes of shelf, gathering not counted.

No workstation or job level sits behind this offer, since the Wandering Trader answers to no village. He turns up near the player unprompted, two leashed llamas in tow, stays for roughly forty minutes to an hour, and leaves again on his own clock whether or not the pickle got bought.

Selling it back to him is not possible. His buying list covers six named items and this is never one of them, so the trade only ever runs from his stock into yours. His inventory is a rolled sample, so the one you find might simply not have it that visit; a name tag removes the despawn timer if the build needs a steady supply.

A full stack costs 128 emeralds across 64 trades, if the trader has that many to sell. Sea pickles cluster together when placed, so a handful bought in one visit is usually enough to light a decent stretch of seabed.

A trader with sea pickle on offer often has other ocean-flavored items too: glowstone, nautilus shell, dye, tropical fish bucket, pufferfish bucket and slimeball.

Sea pickles cluster up to four in a single block, and each one added makes the group brighter. Under water they are one of the few blocks that light a room without a lantern, which is why they end up in almost every coral build.

Bone meal on a pickle standing on live coral spreads more of them across the reef, so a small purchase turns into a supply. Out of water they still glow but far more dimly, and mining one gives the pickle back rather than destroying it.

A sea pickle smelted in a furnace gives lime dye, which is the least obvious dye source in the game and one of the few that does not start as a flower. Given that bone meal spreads pickles across coral, that makes lime effectively farmable.

Out of water they still work as a light, but dimly: a dry pickle glows far less than a wet one, so a build that wants the full brightness has to keep them submerged.

They only generate in warm ocean, on and around coral, which puts them in the same trip as the coral blocks and makes the trader the shortcut for anybody without a reef nearby.