Fishing

Fishing is accomplished by using a Fishing Pole on a body of liquid while having a Bait item in your inventory. By standing on dry blocks and clicking a point over water, a line is cast into the water. Re-click when the bobber moves in order to reel in the line, and hopefully, a caught item.

Requirements


75 connected tiles of liquid are required (1,000 for oceans, 50 for honey). The width of the top row of contiguous liquid tiles (the row where the fishing bobber sits) determines the calculated pond width, and then the depth directly below those is counted. If the pond becomes wider at lower depths, that additional width is not counted. The player may successfully fish in a 1 tile-wide pond, as long as it's 75 tiles deep. The distance of the bobber to the shoreline does not matter.

It is not possible to fish when the player is submerged in liquid, even partially, and even within a completely disconnected body of water. Fishing can however be done while moving, flying, while grappled to blocks, or while standing on top of water, eg. using Water Walking Boots. Fishing can be done in Lava, but requires the Hotline Fishing Hook (not even the Golden Fishing Rod will work in lava).

Quest fishing
Catching a quest fish for the Angler NPC requires fishing in the proper biome and height for the day's current quest, which can be determined by talking to the Angler. You don't need to speak with him beforehand, nor have even encountered him, but the chances of finding the correct area to fish for a quest are much lower without speaking to him first.

The quest fish cannot be caught if the player already has the quest fish in their inventory, nor if the quest fish was already turned in that day. Placing a quest fish in a container instead will allow another to be fished. Saving extras for future quests can save time and potion resources, as quests often repeat. Multiple Quest fish can exist in a player's inventory, but can only be placed there manually from a storage item. Multiples cannot be fished or picked up from the ground by any one player.

Factors
Given the prerequisites for fishing are fulfilled, a number of factors influence the quality/rarity of the caught item. All / percentages listed here combine into a total Fishing Power that determines the chances of higher-quality catches.


 * The Fishing Power of the Fishing Pole used.
 * The Bait Power of the Bait used.
 * Equipped items and Potions.
 * The time the player is fishing.
 * The size of the lake. Lakes with fewer than 300 tiles incur a Fishing Power penalty.
 * When fishing without the High Test Fishing Line, there is always a 1 in 7 chance that the fishing line will break on any reel-in that was supposed to yield a catch (ie. all fishing requirements were satisfied, and a click occurred at the right time). When the fishing line breaks, there is the same chance of consuming bait as there would be with a caught item, but no item is actually reeled in. With the High Test Fishing Line equipped, the line never breaks.

Trout.png Fish
These items can be caught at any time. Most can serve as crafting material for Food and other Potions. Some can also craft other item types, or serve as Bait. Most can be sold to NPCs.

Slimefish.png Quest fish
These are fish items that can be caught only when their particular quest is active, and serve no purpose other than acquiring quest rewards. Their catch chance is arround 1:10. You can determine the day's quest by speaking to the Angler NPC.

Scaly Truffle.png Usable Items
These items can be used directly without further crafting. Some are Tools, while others are Weapons, Accessories, Potions, or Mount- or Pet-summoning items.

Wooden Crate.png Crates
Crates are grab bag-type items that can each contain random loot. They can be right-clicked from within the player's inventory, which will unload their contents. Rarer Crate types contain more valuable loot. Each Crate type can be stacked up to 99 in a single inventory slot.

Tin Can.png Junk
These items have no use or coin value. They can each be stacked up to 99 in a single inventory slot.

Item priority

 * Some biomes override other biomes. The biome order for fishing is: Lava > Honey > Corruption = Crimson > Hallow > Snow > Jungle > Mushroom > Ocean > Forest.
 * Additionally, each biome has its own list of catches that each occupy "rarity slots". Each fishing attempt yields a particular slot. When fishing in overlapping biomes the higher-priority biome's catch occupying that slot will be caught. A fish from the lower-priority biome will only be caught if the higher-priority biome(s) has no fish occupying that rarity slot.
 * Most quest fish occupy the uncommon slot, with the exceptions of the Mirage Fish and Pixiefish, which are rare.
 * Quest fish have a higher priority within their native biome than other uncommon fish.
 * The Ocean overrides all lower priority biomes and defaults to catching Trout. All other biomes default to catching Bass.

Tips

 * A good way to grind for Lightning Bugs is to either convert a large slab of land to Hallow, or one can dig a large hole (lined with dirt) and convert it to Hallow.
 * The most reliable way of obtaining Bait seems to be fishing in a surface forest, at night, close to NPCs: staying still and restricting the spawns to critters will result in a lot of Fireflies spawning, and if alternating fishing and catching it's easy to end with dozens more bait. Water Candles and Battle Potions can be used to increase the spawn rate of critters, while the NPCs still prevent enemy spawns.

Collecting all catches
To obtain all possible catches, at least 13 liquid bodies must be found or created:

Trivia

 * Currently, the Neon Tetra has no use, though it can be sold.
 * The Clownfish quest description is a reference to the 2003 Pixar film, Finding Nemo.
 * The Bumblebee Tuna might be a reference to the "Bumble Bee" seafood brand.

History
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