Probability increase/decrease per level

Hello good lads,

I want to create a system that increases and decreases the probability of finding items per level. What I mean by that is the following.

Let’s say I’ve got a list of 30 items, these items are collectible by the player. Then there’s the player which has a certain level, starting at level 1.

The player, being level 1 should have a big chance of finding the 1st item of the list, a smaller chance of finding the 2nd item of the list etc. etc. with the 30th item being (nearly) impossible to find when being level 1. But then as the player levels up, let’s say the player being level 100, the 30th item should be easy to find and the 1st item not so much.

Currently I do not have a clue how to achieve this, first I started thinking about giving each item in the list a probability, but that means that each item has an increased chance of finding with each level the player ranks up.

I hope you guys can help me figure this out, give me a little shove or a giant push in the right direction.


Create a function that gives you the probability depending on level and item ID. Run it on item drop.