Allows player to choose and play almost all maps with "good" or "bad" rng. This is subjective of course.
For example, in "Go Bank" you can make it all go wrong or have the vault open right away. You decide.

Personally, I use it to make the game more challenging.
This mod is very similiar to "RNG Modifier" by Dr_Newbie,
but it doesn't have an option to choose specific elements as that would require too much effort.