Respiration

Respiration is a rare armor enchantment in Minecraft 1.21. Respiration extends how long you can hold your breath underwater and clears up your vision beneath the surface, letting you work in the deep without drowning so quickly.

Its opening level already delivers a noticeable boost — +15 seconds underwater breathing (30s total) — and it climbs from there to a maximum of level 3 (III) on your helmet.

Respiration tops out at level 3, shown as III on the helmet, and the gap between the levels is where the enchantment's character really lives.

Each of its three levels adds 15 seconds of air, so Respiration III gives you a full minute underwater instead of the usual fifteen seconds. It also slows the rate of drowning damage once your air does run out, buying extra reaction time.

Respiration fits exactly one item — the helmet — and nothing else will accept it, so it is a dedicated helmet enchantment through and through.

Respiration has no exclusivity conflicts at all, so you can layer it onto a helmet alongside every other enchantment that helmet accepts without having to give anything up.

Respiration can be rolled directly at an enchanting table, where reaching its top level of III on a helmet generally wants a fully bookshelf-powered table at roughly level 6. Should the table prove stingy with Respiration, you can instead source the book from loot chest and villager trading and anvil it on.

Its selection weight of 2 makes Respiration a rare roll: it surfaces only now and then on a helmet, so you may need to re-roll several times or simply trade a villager for the book.