Water

Water pools in nearly every biome, thins out in deserts, and cannot exist in the Underworld, where anything you pour evaporates. Its color shifts with the biome you are standing in, which is purely cosmetic and can be overridden with a water fountain. Everything about it is milder than the other liquids: it flows fastest, slows you least, and the danger is running out of air rather than taking a hit.

Landing in water cancels fall damage completely, from any height. It also strips On Fire!, Hellfire and Stinky and blocks them while you stay in it, which makes a shallow pool a real answer to fire heavy fights rather than a novelty. The exception is a snow biome in Expert, where getting wet applies Chilled instead.

The breath meter appears once your head goes under and drains over a few seconds. When it empties you take around 17 health per second until you surface, and it refills quickly as soon as your head is clear. The gear that helps splits into two groups: things that slow the drain, and things that remove the meter.

• The diving helmet and diving gear slow the drain rather than stopping it, as do the jellyfish and arctic versions.
• The breathing reed stacks with those and refills your breath outright whenever its tip is in open air, so it covers anything shallow.
• A gills potion or Neptune's Shell removes the meter completely, which is what you want before an Ocean dive.

By default you sink and wade slowly. The flipper turns repeated jumps into free movement in any direction, though you still drop the moment you stop. Water walking boots and everything they build into, up to terraspark boots, let you run across the surface, and a water walking potion does it for a while without an accessory slot. Landing on the surface that way still cancels fall damage.

For raw speed while submerged, Fishron Wings, the Trident, the Hardy Saddle and the Shrimpy Truffle all restore normal or better movement. The Jellyfish Necklace and the jellyfish diving sets make you glow underwater, which matters more than it sounds because most of your light sources do not work down there.

Fire does not work under water. Candles and most torches go dark, and fire projectiles such as flaming arrows stop giving off light. Water touching a placed torch or campfire knocks it loose entirely, with the cursed, ichor and coral variants as the exceptions. Glowsticks are the standard underwater light because they ignore all of that.

Projectiles also travel noticeably slower through water. Worth accounting for before you commit to a slow weapon in a flooded cavern or an Ocean fight, where the drag can be the difference between hitting a Shark and watching the shot crawl.

• Wet bombs and wet rockets place it. Both can be crafted from their dry counterparts at a sink or a water fountain.
• Water buckets come out of shimmering a craftable sink, or from transmuting a lava bucket.
• Drop an empty bucket on the ground in the rain with no background wall behind it and it fills itself after a while.
• Freeze bombs turn water into ice, and nothing turns ice back, so count that as removal rather than storage.
• A bottomless water bucket ends the question for the rest of the run.

One quirk worth knowing when you move a lot of it at once: the game sometimes fails to level out a large volume that has just flooded a new space. Leaving the world and coming back runs the settle pass again and usually fixes it.