Randomness and games at it seems goes hand in hand. We can use it as a game mechanic or to create procedural content. Have to much and players will flee from your game as lazy person flees from responsibility. Have to little and the game might become too predictable or too difficult.
Randomness in video games is as called pseudo randomness… It’s not really random but based on a mathematical formula often based on time. We can of course implement different types of formulas to get the type of randomness we like.
Let’s start with the math side of randomness and down below you’ll find the game design part.
Math behind Randomness
This video from the Coding Math channel goes through the math of weighted randomness. This means how to generate random values with different odds for different values.
If you are using the Unreal Engine you can read their documentation on Distributions here.
For unity unless you want to implement it yourself there are a few assets for randomness and weighted random, the most current being these.
and a few outdated ones but should still work (no guaranties).
Game Design Randomness
There is a lot to say about randomness when it comes to game design and this article I think sums it up great and with some detail. Keith Burgun talks about what randomness is, the different types and how it all relates to game design.
And the last thing a want to mention is a tool I find really useful for the design part, and that is AnyDice.com, it’s an online tool to test in a visual way the curves for different dice combinations. AnyDice is a great resource for all designers.