Fishing

Requirements
75 connected tiles of liquid are required (1,000 for oceans, 50 for honey). The width of the top row of continuous 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 will only work with the Hotline Fishing Hook.

Fishing Quests
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. Quest fish cannot be caught if the player already has that particular quest fish in their inventory, nor if the quest fish was already turned in that day. However, if you put the Quest fish in your safe/bank then you may catch another Quest Fish. You can then transfer the Quest Fish to a chest if you wish. The Angler gives out special rewards when a proper quest fish is turned in.

Factors
Given the prerequisites for fishing are fulfilled, a number of factors influence the quality/rarity of the caught item. All are combined into a total "Fishing Skill" that determines the chances of higher-quality catches. Percentages in the tables below that influence Fishing Skill are marked or.


 * 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. (note that all the factor of time is multiplied with the bait power above, and will round down after the calculation of each one).
 * 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 reel-in, forfeiting the caught item. Chances of consuming bait remain the same even if the line breaks. With the High Test Fishing Line equipped, the line never breaks.

For example, if you have the Golden Fishing Rod, Master Bait, equiping full Angler set and Angler Earring, with the buff of the Fishing Potion, and it's Raining, at 5:00 am, at New Moon, your fish power will be calculated as following: So, you have 196 fish power.
 * 1) Add the fishing power of the Fishing Rod, Bait, Equipment and buff, so it's 50+50+(5+5+5+10)+15=140.
 * 2) Apply the influence of the weather: 140*(1+20%)=168.
 * 3) Apply the influence of the time: 168*(1+30%)=218.4, round down, 218.
 * 4) Apply the influence of the Moon Phase: 218*(1-10%)=196.2, round down, 196.

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. Jellyfish can be used 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 around 1:10. You can determine the day's quest by speaking to the Angler NPC. There are 39 distinctive variants of quest fish.

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. You will only "catch" these if a lake is too small or if your Fishing Power is too low. When a lake is at least 300 tiles (200 for honey) in size or your total fishing power is at least 50 you will no longer catch junk.

Mechanics

 * Some biomes override other biomes. The biome order for fishing is (if you are in both Corruption and Crimson, there will be 50% chance to be considered as Corruption and 50% for Crimson each time it attempts to generate a fish):
 * Lava > Honey > Corruption = Crimson > Hallow > Snow > Jungle > Mushroom > Ocean > Forest(including sky, surface, underground, cavern, etc.).
 * NOTE: Possible catches determined by biomes have different priorities from how the music plays. The background music of Terraria is misleading because its priority for music is:
 * Ocean > Mushroom > Corruption > Crimson > Jungle > Snow > Hallow > Others
 * Because the music priority is drastically different than the fishing priority, this may explain why you could not find a quest fish in a part of the world that is playing the music for the biome that fish could be found in. (For example, you stand where Jungle and Snow overlaps, so you will hear Jungle music but harvest Tundra catches.)
 * There is inconsistency in the mushroom biome criteria. Note that 200 mushroom tiles is considered valid when it refers to fishing, while for other uses 100 is mostly enough.


 * The game will attempt to generate a fish each tick with probability (fishing power + 75)/2 %, reaching a cap at 125 fishing power.
 * 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.
 * The chance for yielding a particular slot is detemined by player's fishing power, the higher the fishing power, the higher the chance for each slot. The fomular for the chance is listed below (the denominator of each chance caculation will be round down):
 * 1) Common: 1/(150/fishing power), capped at 1/2 (at 51 fishing power).
 * 2) Uncommon:  1/(300/fishing power), capped at 1/3 (at 76 fishing power).
 * 3) Rare: 1/(1050/fishing power), capped at 1/4 (at 211 fishing power).
 * 4) Very Rare: 1/(2250/fishing power), capped at 1/5 (at 376 fishing power).
 * 5) Extremely Rare: 1/(4500/fishing power), capped at 1/6 (at 643 fishing power).
 * Most quest fish occupy the "uncommon" slot, with the exceptions of the Mirage Fish and Pixiefish, which are "rare". However, quest fish have higher priority within their native biomes than other fish.
 * Some fish may occupy more than one slot, and also some fish may have an additional chance to lose even if it gets the slot. For example, the Toxikarp occupies the Extremely Rare slot, but even when in the slot, there is also a 50% chance failed to obtain it.
 * The Ocean overrides all lower priority biomes and defaults to catching Trout. All other biomes default to catching Bass.
 * Once you got a fish, it will wait for 1.5~4 + fishing power/60 seconds for another attempt.

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.
 * On some nights, many fireflies will spawn in the area around NPCs; however, if several NPCs live in the hallow, the same effect can occur with lightning bugs. This seems to happen on any night when fireflies are spawning in large numbers.
 * A good way to grind for Bait is to create a jungle farm, to allow and break the plants that grow, due to the high odds of getting bait per plant. Possible drops are Grubby, Sluggy or Buggy.
 * 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. Alternatively, if one obtains Flower Boots from a Jungle Shrine, they can stand on grass with a yoyo or flail and have the plants spawned by the boots be constantly destroyed, generating many worms and grasshoppers.
 * There are a total of 16 different fishing locations that can yield distinct catches: Surface: Forest, Ocean, Jungle, Corruption, Crimson, Hallow, Snow, Honey; Underground: Forest, Snow, Hallow, Jungle; Cavern: Snow + Hallow/Corruption/Crimson; Floating Island; Any Layer: Lava, Mushroom.
 * Since quest fish cannot be fished or picked up when that same quest fish is already in the player's inventory, duplicate quest fish can be saved in Chests or other storage items, which can be useful since quests often repeat. Duplicate quest fish can however be placed in a player's inventory manually by moving them from Chests afterward.
 * An easy pre-hardmode way to tell if it's a full moon, and thus an ideal night to fish, would be to use a Deathweed's blooming as an indicator. A Deathweed only blooms under either a full moon or a Blood Moon, therefore -unless a Blood Moon is currently occuring- if the plant blooms when placed in a Pot, it means the Moon is full.
 * It's a good idea to save up your crates until hard mode has been activated because of their chance to drop hard mode bars this can make your character much more survivable in expert mode.
 * The quest is the same for every character every day. The quest fish can also be stored in a chest - you can use one character to fish up and then piggy bank the quest fish and then fish up another and bank it over and over, then move the fish from the piggybank to a chest back in the house - and then use other characters to log in, grab the fish, then complete the quest. Rather than making different worlds to do the daily you can use different characters to drasticlly increase the number of fishing completes per in game day.
 * If you have a very high fishing power (Master Bait, Golden Fishing Rod, along with fishing buffs and equipment) it is possible to have a net gain of Master Bait from the crates obtained.

Trivia

 * The Neon Tetra and Golden Carp have no use, aside from their coin value. The Golden Carp is especially valuable at.
 * The Clownfish quest description is a reference to the 2003 Pixar film, Finding Nemo.
 * The Batfish quest description is a reference to the iconic Batman Theme.

History
Pêcher 낚시 Рыбалка