Luck is a brand new mechanic introduced in Terraria 1.4, Journey's End. It is a complicated system that is mostly hidden from the player, at least until you meet the Wizard in Hardmode. Good luck or bad luck essentially has an effect on all drops, mob spawns and biome-unique spawns. \n \nThere are new lucky and unluck debuffs, available from Ladybugs, Potions and from Torches. The Ladybug luck buff is achieved by touching a ladybug caught and then released by a player, and it can have a huge effect on the RNG drop rates of items. However, it is the Torches that have got everyone a little annoyed... \n \nhttps:\/\/www.youtube.com\/watch?v=H77Zfzy4LWw \n \nGrinding for mob drops is a key part of Terraria and always has been. RNG also has an impact on whether or not you find the rare NPC spawns, such as the Tinkerer, and getting your hands on rare Traveling Merchant items. \n \nThe new Torch mechanic is based on placing biome appropriate torches in the right biome. For example, Desert Torches in the Desert Biome will increase drop rates (luck) by a small margin (arbitrarily given the positive value of 1.) However, placing regular torches has a negative impact of 0.5. \n \nThis poses a few problems. Firstly, new players to the game that haven't heard of the luck system will be randomly placing neutral torches all over the place, having a negative effect on their chances of finding anything interesting in certain biomes. \n \nSome of these torches also make the areas harder to see - the Ice Torches give out Blue light in an otherwise totally blue area, the underground Ice Biome. \n \nAnd even if you do use the correct torches, it's basically impossible to judge how lucky\/unlucky you are. There are no meters or measures to tell you your luck score unless you speak with the Wizard, and even then it is not clear unless you learn his tips by heart. \n \nLuck has a huge impact on gameplay, as there is a rolling RNG mechanic incorporated into the values. In Terraria there is a chance of discovering random encounters, items and other drops. \n \nHaving a positive luck score increases the chance of these random events occurring. This covers everything from finding Coin Portals in Pots to discovering Pinky somewhere on the map. \n \nWith a high luck score, the chance of discovering rare drops or NPCs can be increased up to 20%. With the lowest luck score, the probability is decreased all the way to 6.5%. Pretty huge difference, right? \n \nWith such a huge changelog for Terraria 1.4, it might have been easy to miss such a huge change as this one. The new luck mechanic is still causing some heated discussion across social media, and some really aren't happy with the poor implementation of the system. \n \nAs of the new hotfix, bad torch luck has been removed from the game after Re-Logic responded to player feedback.