Luck is one of eleven player Skills. It is related to the art of getting better stuff from treasure chests. Note that your luck skill level only affects your chances of getting better loot. It has no effect at all on your chances of finding paintings, diamonds, onyx, or any other desirable items that automatically generate (or, more often, don't) when worlds are created.
While increasing luck does not guarantee that you'll always loot rare items, higher luck levels will allow you to loot rare and semi-rare items more often, and occasionally even very rare items. In fact, certain items only become lootable once you've reached a high enough luck level. What those levels are, and what items become lootable at each level, remains one of Deepworld's most enduring mysteries.
Raising this skill allows you to:
- Loot larger quantities of items
- Have a greater chance of looting higher quality items
Skill Bonus (Accessories)
Max Level: 13
Luck Skill (10) + Rabbit's Foot (3)
Luck Skill and Loot Quality
In all cases, no matter how you get loot, it will be affected to some degree by what level of luck skill you have. Higher luck skills will increase your chances of getting better loot, and will increase the quantities of those loot drops that are quantified. Furthermore, each added level of luck adds additional items to the possible items you can loot. In other words, some items can only be looted if you have a certain level of luck.
To date (February 2016), no one has come up with a reliable list of which loot items are available at which luck level. Nor has anyone laid out the details of the probability formulas that the developers use to determine exactly what loot will drop in every player's circumstances.
(Note that the following analogy does not necessarily accurately represent how luck works in the game. There are other ways loot might be calculated. What follows just an attempt to make the whole probability thing a little more concrete in general.)
One way to think of this is to imagine that every chest you loot is a black box with a hundred marbles in it. There are four possible marble colors -- red, blue, green, and yellow -- and each color represents loot rarity, with red being common, blue being uncommon, green being rare, and yellow being very rare.
Now imagine there are 70 red marbles, 20 blue, 9 green, and 1 yellow in your black box. You stick your hand in and randomly pull out a marble. You get lucky and pull out the yellow one. Yay! You're guaranteed now to get a loot drop that the game classifies as very rare!
So you go to the marble exchange machine and drop it in the slot. The machine reads what level of luck you have, and then randomly chooses from the pool of "very rare" items that are available to someone at your luck level.
A different level of luck will start with a black box that has a different distribution of colors. For example someone with a higher luck level might have a box with 40 red marbles, 30 blue, 5 green, and 2 yellow. The goodies associated with each color of marble will be different for different levels, too. A person with level 5 luck might have 20 different options of "rare" items, for example, while a person with level 13 luck might have 40 different "rare" possibilities for the game to randomly choose from.
As your luck level goes up, the number of different types of rares you can loot increases. Players don't know the exact distribution of this, but we do know that raising your luck level always expands your loot possibilities (at least up to luck level 10). You're able to loot everything you could loot at the previous level, with some new additions.
In addition, your chances at getting really great loot will reset with every chest you loot. Every chest you loot is a brand new black box. So if there's only a 1% chance of randomly grabbing that yellow marble, every time you loot a chest, you have a 99% chance of NOT getting it.
And on top of all that, the game may define something as "very rare" that you, personally, think is crap. Maybe you don't care about compasses, for example. The game still thinks they're very rare, and as a result, depending on what your luck skill level is, compasses will take up a slot (or perhaps even five slots, one for each type of compass!) in the "very rare" inventory that the game uses to award your loot.
The most important thing to understand about loot is that it's far more dependent on your real-life luckiness than it is on your in-game luck skill level. Luck skill only helps shift the probabilities around a little. Even if there are 95 yellow marbles in that box, if your real-life luck really sucks, then you're going to pull from that 5% of crappy marbles again and again.
Does Level 10 Luck Give Better Loot Than Level 13?
Your chances of getting better loot get better as your luck level increases. So why do some players swear that higher luck levels are worse than lower ones?
To answer this, let's pretend we're back in the early days of the game when skill levels only went up to 10 and it was possible to loot onyx. Note that we are JUST PRETENDING. You cannot actually loot onyx. Do not go stampeding back into game to change your luck to level 8 in hopes of looting onyx.
Back to the explanation: Pretend that in order to loot onyx, you need at least level 8 luck. And at level 8 luck, let's say your black box contains 3 yellow marbles, and that if you get a yellow marble, the game randomly chooses from 10 different possible items tagged as yellow, one of which is onyx. This means you have a 3% chance to get a yellow marble to begin with, and if you manage to get a yellow marble, you then have a 1 in 10 chance of getting onyx.
Now imagine raising your luck to level 10 changes your marble distribution so that now instead of just 3, there are 5 yellow marbles in the box. But another thing has changed, too: the number of yellow-level items for the game to pick from has increased. At level 8 luck, there were only 10 possible yellow items. But now at level 10 luck, there are, say, 30 different possible yellow items instead of just ten. This means even though you have a 5% chance of getting a yellow marble, once you do have that marble, you now have only a 1 in 30 chance of it yielding onyx.
Here's the hitch, though. The last official word on the subject was that at luck level 10, your pool of very rare items stopped expanding, and all that happened was your chances of drawing a yellow marble increased. If that remains true, then your chances of looting the very rare item that you want the most is better at luck 13 than at luck 10, because you have an increased chance of getting that yellow marble to begin with, and the number of yellow-tagged items remains the same.
Another thing that factors into the perception that level 13 luck is better than level 10 is that when you have lower luck, you're not really expecting to get lots of fabulous loot, so when you DO get a really good thing, it's a surprise, and you're more likely to remember that one surprising event than you are to remember all the times you didn't get the best things. The reverse is true when you have the highest possible luck level: you might unconsciously expect to get more rare things, so every time you get really crappy loot, it's a surprise that goes against your expectations. This, in turn, means you're more likely to remember that moment of surprise at getting junk than you are to remember the times you got good -- or even really good -- stuff. Put it all together and you end up with a strong feeling that level 13 luck is worse than level 10 luck, regardless of what the statistical facts might be.
When all is said and done, players just don't have enough information to figure out the exact mechanics of how the luck skill affects loot. Never mind that the developers continue to quietly tweak these mechanics as new server releases roll out. We do know that raising your luck level is always going to increase your chances of getting good stuff in one way or another. But no matter how high your luck level, there's no guarantee that you'll get good stuff all, or even most, of the time. Part of what makes the rarest loot drops so exciting is that they're so rare. You have to be lucky -- in game and in real life -- for all the stars to align in just the right way.