Terraria Luck Mechanic Guide

Hello from our Terraria Luck Mechanic Guide. We will list all the sources, from simplest to most complicated. Following that is a description of how lucky benefits you.

This is the guide kurioshopp it was created by. You can find the author’s link at the end of the guide.

Terraria Luck Mechanic Guide

Welcome to our Terraria Luck Mechanic Guide. This guide will show you detailed information about The Luck Mechanic of Terraria!

The Luck Mechanic of Terraria about:

• Luck is a secret mechanic that usually helps you when something has a chance of happening.
• It’s pretty complicated behind the scenes and is not explained in the game.
• If you have a high luck modifier, you can get most monster drops, get most lost npcs, encounter some rare enemies, get a few boss drops outside of bags, see rare items at the Traveling Merchant, and encounter coin portals all at a higher rate.
• You can also improve your fishing power, reduce damage taken, and improve damage dealt.
• Luck generally doesn’t penalize you (ladybug and Town NPC killing excepted) and can be increased in a fairly reliable manner. Its effects are fairly strong when positive and the negative luck is short-lived.
• Luck does not help you dodge, save ammo, encounter events, get better items out of containers and grab-bags, or other things. It also does not directly improve your odds of fishing up any specific items.
• Not interacting with the luck mechanic is just fine and will not stop progression, but if you do work with it you will have an easier time.

Luck Modifier Sources

Galaxy Pearl Luck

+0.03 – Having consumed a Galaxy Pearl with your character before.

Gnome Luck

+0.2 – Being within a 170×125 rectangle of at least 1 gnome statue.

Lucky Coin Luck

+0.05 – One of lucky coin and its upgrades are equipped on you or a same-team player within 50 blocks.

Lucky Horseshoe Luck

+0.05 – One of lucky horseshoe and its upgrades are equipped on you or a same-team player within 50 blocks.

Lantern Luck

+0.3 – Lantern nights (after killing any boss) increase luck everywhere in the world while active, but do not start or apply while a boss is alive, moon lord is being summoned, an invasion or other event is active.

Potion Luck

+0.1–0.3 – Luck potions add +0.3 luck when there is more than 10 min left of the buff, +0.2 luck when there is between 5 and 10 minutes left of the buff, and +0.1 luck when there is less than 5 minutes left of the buff. The duration is the only technical difference in the potions of luck and each type does not stack with the others or raise the remaining duration above the base duration.

Coin Luck

+0.05–0.2 – Coin luck is granted based on how much money you have thrown into Shimmer, and has a counter that decays over time at a rate of 0.01% each tick.
It maxes out at 1,000,000 which is granted by a platinum coin, lasting 3m 51s.
A gold coin grants 10,000 to the counter, a silver coin grants 100, and a copper coin grants 1 (this is an equivalent exchange rate of 1 counter point per your money’s value in copper).
At a counter value of 0.25 the luck is turned off instead of decaying further.
You will have the maximum bonus of +0.2 luck when the counter is above 249,000 (24.9 gold) and it scales in some fashion once it falls below that, down to the minimum of +0.05 luck when less than 2.49.

See the wiki.gg for the scaling table, but in summary the more money you throw in the longer the effect lasts and the greater the benefit.

Ladybug Luck

• -0.4–+0.4 – Ladybug luck is based on touching (walking into/past) ladybugs for good luck and killing/using as bait for bad luck. It ranges from a significant luck penalty to a high bonus based on these rules:
• Touching a naturally spawned ladybug grants +0.2 luck decaying linearly toward neutral over 12 minutes (double these values for gold ladybugs).
• Killing the Guide while not having any negative ladybug luck grants +0.067 luck decaying linearly toward neutral over 4 minutes.
• Killing a ladybug within 6.25 tiles or consuming a ladybug as bait (at the moment it is lost) grants -0.05 luck decaying linearly toward neutral over 3 minutes (double these values for gold ladybugs). Over 6.25 tiles away, the penalty quickly reduces to zero at 25 or more tiles away. While decreasing luck, this also increases the chance of rain for 30 seconds stacking up to 300 seconds.
• Killing a Town NPC (other than the Guide or Clothier) grants -0.067 luck decaying linearly toward neutral over 1 minute.
• Positive and negative values are tracked separately and you cannot have both at the same time.
• Whichever duration is greatest is what counts down, meaning new ladybug luck sources do not add duration but will replace the duration if they are longer.
• Having a positive ladybug luck value currently applied cancels any active negative ladybug luck you may have or receive for the duration (except the Guide kill).
• Killed or consumed-as-bait ladybugs and NPCs only apply luck to the player that caused it, and non-player kills do not count.
• All of a player’s ladybug luck is reset to neutral when that player leaves the world.
• Using ladybugs for crafting (luck potions and the cage) does not affect luck.
• See the wiki.gg for the detailed breakdown of the math.

In summary, to maximise luck touch naturally spawned ladybugs (Forest towns on windy days). Avoid killing NPCs when you need luck, except the Guide or Clothier. You can avoid killing ladybugs by having an active Guide to Critter Companionship or its upgrade, though this will not protect you from using them as bait.

Torch Luck

• +0.1–0.2 – Torch luck depends on a lot of rules; here they are:
• Torch luck is granted as the result of the sum of bonuses and penalties; the total bonus maxes at +0.2 and the total penalty maxes at -0.3, although the resulting luck modifier is a bonus that cannot be less than 0 regardless of negative luck.
• Each torch increases or reduces luck by +0.2 (exceptions apply).
• In Underground, Caverns, and Underworld, torch luck is applied by being within an 81×81 rectangle of a torch that “matches its biome” (exceptions apply) and simultaneously NOT being within that same radius of a torch that “does not match” (exceptions apply).
• Torches in a hybrid biome such as Hallow Desert do not count against you if at least one of the biomes in the hybrid matches.
• In Dungeon and Jungle Temple, no torch luck applies.
• At Surface or Space elevations, only torches being held apply and only to the holding player, including penalties and Bone torches.
• Colored, Ultrabright, Demon, and Aether torches, alongside all other light sources, have no effect.
• The exceptions to rules 2 and 3 are as follows:
• Cursed and Ichor torches do not count against torch luck outside their biomes, but still give the benefits of Corrupt and Crimson torches when in their biomes.
• Coral torches do not count against torch luck outside their biome if they are in water.
• The typeless, basic, etc. torch does not increase torch luck. Each of these gives a penalty of -0.1 luck in the Desert, Corruption, Crimson and Hallow. They give a penalty of -0.3 each in Snow.
• Bone torches have no biome, cannot count against torch luck, and give 0.1 luck each when outside Snow, Desert, Jungle, Corruption, Crimson, Hallow, Dungeon, or Jungle Temple. This allows you to gain luck at all elevations (Space, Surface, Underground, Caverns, and Underworld) when they are Forest (plain, or untyped). They also apply in the Ocean and Mushroom despite those having their own torch.

In summary, maximizing luck requires you to use biome torches underground in their matching biome, bone torches at boundaries or in plain areas.
Avoid using any non-Bone torches within 81 blocks of the wrong biome including at surface elevations, except Coral torches are fine underwater and Ichor, Cursed, Colored, Ultrabright, Demon, and Aether torches are acceptable anywhere.

As a side note, Torch-God’s Favor applies different rules to torch (and campfire) selection:
Demon torches are placed in Underworld and Aether torches are placed in Aether (when surrounding biome torches or Bone torches would apply).
Ice torches will be placed near Snow even if you are still in Jungle or Mushroom for spawning, etc. purposes.
Coral torches are not placed in the Ocean despite giving a bonus there.
Bone torches are placed in the Dungeon despite torch luck not applying there.

Luck Modifier Applications

What is the best outcome achievable for luck, and what is the most reliable way to be lucky?

The maximum luck value you can attain is 1.73, however the maximum applicable luck is 1. Therefore, you can achieve maximum effective luck bonus without relying on lantern nights (sometimes not allowed to apply) or ladybug touching (which is a random availability). if you maximize all other sources, including using luck potions, coin tossing, torches, gnome statues, and accessories, you will reach a luck of 1.03. The galaxy pearl luck contributes exactly 0.03 of that, and so with only the maximized sources in the previous sentence you will reach exactly 1. This galaxy pearl luck does cover a bit of the decaying coin luck, however, and also applies even when you are not trying to maximize luck, so it is well worth it.

How does luck affect probabilities?

The luck value acts as the percent of the chance to gain in a probability of a positive result on certain rolls, that is, higher luck means you are more likely to get a “good” outcome. For instance, luck of 1 means 100% chance of gain in positive result probability, 0.5 is a 50% chance of gain in positive result probability, -0.4 is a 40% chance of a gain in negative result probability, and so on. The positive or negative outcome probability gain is random based on a complex formula for which I again refer you to the wiki.gg. Luck of zero means no affectation of the positive or negative result.
When a probability takes luck into account, it uses the luck of the closest player, with few exceptions.

What probabilities are affected by luck?

Item drops from defeated enemies are affected by luck, including coins, health and mana drops. Some items are unaffected however:

• Items guaranteed to drop and items dropped by grab-bag type items are unaffected by luck.
• Basic feathers dropped by harpies have a fixed 50% chance.
• Any time a boss or biome mimic is guaranteed to drop one item out of a subset, it is unaffected by luck.
• Specific other boss drops (including some from the previous rule) are also unaffected, including from the Wall of Flesh (emblems and weapons only), Slime King and Queen (hooks only), Deerclops and Moon Lord (weapons only), and Queen Bee (bee clothes and weapons only). All Old One’s Army drops are also unaffected.

NPC spawns are affected by luck. This includes golden critters replacing regular ones (also shaken tree spawns), dungeon spirit spawns, hardmode dungeon enemies spawning outside of their typical wall type, and the following entities where their conditions are otherwise met:

• NPC Quests: Bound Goblin, Bound Wizard, Old Shaking Chest, Mystic Frog, and Clumsy Balloon Slime.
• Critters: Fairies, Enchanted Nightcrawler, Prismatic Lacewing, and Truffle Worm.
• Enemies: Golden Slime, Pinky, Gnome, Ice Golem, Doctor Bones, Dungeon Slime, and all variations of Chest Mimics (not Present Mimics).

What else is affected?

Certain other mechanics are also affected:

• Coin Portals spawning from broken pots.
• The player with the highest luck currently in the world will affect the items sold by the Traveling Merchant.
• Damage calculations (before defense) are altered up to 5% on average, including in PvP. Note that this does result in luck inversely affecting benefits from reflected damage such as thorns effects and parries.
• Fishing power is multiplied by 110% to 140% (positive) or 60% and 90% (negative).

What isn’t affected by luck?

Certain mechanics are definitely not affected, however:

• Boss drops as above.
• Grab-bag items drops such as boss bags, oysters, and crates, as above.
• Standard harpy feathers, as above.
• Dodge mechanics from armor and accessories
• Ammo conservation/consumption rate
• Event occurences
• Health and mana recovery
• Buffs and debuffs
• Most anything else, etc.