Liquids

There are currently 3 types of liquids in Terraria, each with varying properties: Water, Lava, and Honey. All of these have common "liquid mechanics", but each also has distinctive features.

All liquids can be fished in. For each liquid, the pool must contain a minimum number of tiles for fishing to work (See the Fishing page for full details). Lava requires a special fishing rod to fish in it, the Hotline Fishing Hook. Lava and Honey have a limited selection of fish that can be caught in them.

Flow and Duplication
Liquids can flow between tiles, and can fill part or all of a tile. Liquid in motion is considered "flowing", and can visually occupy more of a tile than it will when it comes to rest. Liquids that are not moving are considered "settled". At each game startup, all flowing liquids are explicitly settled, moving them to their natural destination. Water flows most quickly, lava is slower, and honey flows the slowest. If a liquid block is placed with open space beneath it, it will flow downwards. If it has a block below it, but open space to either side, it will flow to either or both open sides, resulting in partial tiles of liquid. However, there is a minimum depth for liquid tiles; if the liquid spreads too thinly, it will disappear altogether.

As liquids flow, their volume tends to increase. This can be exploited to duplicate liquids indefinitely (see below). Note that it is much harder to get rid of liquids; there is a Hardmode tool to remove water within reach (see "Water" below), but otherwise the only ways to destroy liquids are by pouring a block or so over a large flat space, or by letting them combine into blocks. However, if small amounts of one liquid are poured over a pool of another, even a single bucket's worth can solidify much larger amounts of the target liquid.

Moving Liquids
Buckets and Pumps can be used to collect, move and place liquid around. Full tiles of liquid, or partial tiles at least 50% full can be picked up with a bucket, and will fill the bucket even if it was a partial tile. When a bucket is full, using it will always place a full tile of liquid. Full buckets can be stacked up to 30, and placed in inventories, chests, etc. like any other item. Pumps are mechanisms, used with wires and various triggers. When an input and an output pump are connected with wire and triggered together, they will transfer up to four tiles of liquid from input to output. Contrary to previous reports, they cannot directly duplicate liquids, but they can certainly be used to keep a liquid continuously flowing, which will tend to increase its amount over time. Liquids can also be purposely poured over blocks to split their flows, which maximizes the volume increase from flow.

Interactions with blocks
Liquid cannot be placed in a tile containing a block, even if the block has been hammered into a partial block. If a liquid tile is adjacent to the empty part of a partial block, it can appear to fill the space, but is not considered "in" the block's tile, and cannot be picked up from there. Blocks can be placed in liquid (except lava). Any liquid in the tile will be trapped, and cannot flow out (or otherwise be interacted with) until the block is removed.

If a full tile of liquid is next to a half block with open space on the other side, it will visually flow over the block and continue as a river or waterfall (including lava or honey). This waterfall is purely a visual effect, and cannot be interacted with (a "lavafall" of this sort will not burn the player, nor a "honeyfall" heal them). If the liquid is water and the half-block is a Gemspark Block or Rainbow Brick, the waterfall will glow with the color(s) of the half-block.

At various points in the world, liquids (or sand) can be found dripping from ceilings. This dripping effect is purely visual, and has no functional use. This effect can be created by the player using Magic Droppers. Natural or player-made "droplets" can be broken (but not harvested) with a pickaxe, aiming just below the block they drip from.

Liquids can be stored temporarily within Bubbles, which are otherwise furniture-like, but displace liquids as if they are blocks. Upon restarting the world, the liquid will be freed, allowing it to fall (it is wise to remove lava from bubbles before exiting the world). Bubbles can also be used to support liquids in midair (again, as if they were blocks), and these will not fall when the world is restarted.

Players and liquids
Players normally cannot walk over liquids, and will instead fall in. Falling into liquid negates all fall damage regardless of distance. Players entering/exiting liquids will make a splashing sound and appropriate animation. Certain items can allow walking on liquids (see below); the player still won't take fall damage when landing on the liquid. While in liquids players will find their movement slowed. The slowing effect matches the liquid's flow speed: Water is least restrictive, lava is in-between, and honey is most restrictive.

Players have no natural ability to swim in liquids, but can still jump or fly according to their current equipment. Certain items can cancel the movement penalty (only for water) and/or allow free swimming, see below for details. Flippers (or upgrade) will allow the player to swim freely in any direction. However, it does not allow them to float, and as soon as they stop moving they will sink down through the liquid. The Neptune's Shell and its upgrades will allow the player to swim freely in water or honey, but not lava. Note that neither landing in nor jumping out of liquid (including swimming up past the surface), will reset flight time for Wings or Rocket Boots variants.

A player who stays submerged too long in water or honey, will begin to drown. When the player first goes above neck level in the liquid, the Breath meter will appear, and slowly empty. When the meter empties completely, the player will begin to take damage (about 17 health per second). When the head of the player emerges from the water, the breath meter will rapidly refill and then vanish. Various equipment can prevent drowning: A Diving Helmet (or any of its upgrades) will slow the emptying of the breath meter. The Breathing Reed will do likewise (and stack with the diving equipment); it also reaches above the player's head, and if the end of the reed is in air, the player can refill their breath meter. A Neptune's Shell (or its upgrades) will remove the breath meter and prevent drowning in water altogether.

Crafting With liquids
When different liquids touch each other, they create one of the three contact-created blocks: Obsidian (water+lava), Honey Block (water+honey) and Crispy Honey Block (honey+lava). When this happens, up to a tile's worth of each liquid will be consumed, but either or both of the touching tiles can be partial and/or flowing tiles -- that is, creating the block does not require a "full" tile of either liquid.

Furthermore, liquid tiles are minor Crafting stations, which enable a few recipes whenever the player is nearby. Their recipes do not use up the liquid, even when filling Bottles with water or honey.

Water
Water is by far the most common liquid in the game, appearing in lakes from the edge of Space to the depths of the Caverns. (Lower in the caverns, lava takes over as the primary liquid, but some water still appears.) However, if water enters or is placed in the Underworld, it will rapidly evaporate.
 * Water does not usually provide any buffs or debuffs, but entering water will remove the On Fire! debuff. In Expert mode, entering water in a Snow Biome will apply the Chilled debuff.
 * Pools of water can spawn critters (usually Goldfish) or enemies depending on depth and biome.
 * The color of water varies depending on the biome the player is standing in; this can be altered by use of a Water Fountain.
 * Water Walking Boots, or any of their upgrades, will allow walking on the surface of (non-flowing) water.
 * A Neptune's Shell (or any upgrade thereof), or Fishron Wings will almost completely remove the slowing effect of water (only).
 * If large amounts of water are poured into the Underworld, (e.g., diverting a lake or ocean), eventually all the water will evaporate, but this can take some time, and it will convert the lava surface to obsidian.
 * There is no way to "melt" ice or snow into water, nor the reverse. Therefore, the amount of Ice in a world is limited. However, water can be produced endlessly, if you obtain the Bottomless Water Bucket. The Super Absorbant Sponge can be used to remove water infinitely.

Lava
Lava is the second most common liquid in the game. It appears often in the lower Cavern layer, and is plentiful in The Underworld. It can be created in two ways:
 * If Hellstone is mined in the Underworld, each block drops a half bucket/tile of lava (a full bucket if in Expert mode).

Lava will deal direct damage to the player on contact, and inflict the On Fire! debuff. However, the player cannot drown in lava. The Obsidian Skin Potion or Lava Charm/Lava Waders will prevent contact damage for their duration, and an Obsidian Rose will sharply reduce the damage. Lava's contact damage is reduced by a player's defense, so advanced armor can be quite helpful. Lava will also burn most enemies, and so can be used in traps.
 * If in Expert mode, killing Lava Slimes will drop lava.
 * Lava is opaque, and will hide both objects and creatures, including the player.
 * Blocks cannot be placed in lava, but "falling blocks" (Sand, Silt, and Slush) can fall into it and thereby be placed at the bottom. This can be used to build a pillar for bridging the lava.
 * Lava can destroy items. Most items can be destroyed if submerged in lava past the midpoint of its sprite. However, an item of Blue rarity or higher will not be destroyed regardless, and there are a few other items which are immune to lava: Obsidian, Fireblossom seeds and herbs, and Living Fire Blocks of any type. The depth of a lava moat can be tweaked to destroy only copper coins, see the Lava page for details.
 * Flowing lava will dislodge most platforms and furniture, which may then be destroyed as items. Pumps, Statues, Obsidian Platforms and Obsidian furniture are unaffected.
 * Lava Waders will allow walking on lava indefinitely (if the surface is settled), and even allow swimming in it for 7 seconds.
 * Flippers or their upgrades (Diving Gear etc) allow swimming in lava, but will not help with the movement speed or contact damage. The Neptune's Shell and its upgrades do not work in lava.
 * Placing Hellstone in the Underworld and then mining it again creates lava, effectively producing an endless amount of it.

Honey
Honey is the rarest liquid in the game, and is naturally found only in and around Beehive Mini-Biomes inside the Underground Jungle. It can be created by mining Hive Blocks, but if honey is produced, the Hive Block is used up. Honey will slow the player's movement a great deal (as will the Honey Blocks often found nearby).
 * Honey is nearly opaque, hiding submerged items and creatures.
 * Honey pools will provide the player with a special life regeneration buff. This effect lasts as long as the player is standing/swimming in honey, then another 30 seconds after they leave the honey. The player does not need to be submerged, but the honey pool must be at least two tile's worth, and not too shallow. There are also a couple of "healing potions" to be produced at honey pools, namely Bottled Honey and Honeyfin s.
 * Like water, the player will drown in honey if submerged for too long. The same items that slow or prevent drowning in water, will do likewise in honey.
 * The same items which allow walking on water (Water Walking Boots or any of their upgrades), or swimming in water (Neptune's Shell or Flippers, or their respective upgrades) will work the same in honey. However, they will not prevent the slowing effect of honey (Fishron Wings will however).

Infinite Liquids
Using Pumps, a player can construct infinite liquid sources, by pumping liquid in a continuous cycle. To the right is an example of a compact infinite liquid factory, with arrangements to produce the contact blocks as well. Note the enclosed storage to prevent overflowing and the 1-second Timer to automate the process. The double output pumps do not (as formerly thought) duplicate the liquid from the input. However, they may still help speed, by carrying overflow liquid when the first output pump is blocked (that is, the liquid it brought in last cycle hasn't had time to flow away).

液体 Liquides