A script made for RPG Maker VX Ace to simulate Undertale's "after-game memory"
Just copy the script in a section above Main (right where RPG Maker suggests you to put it!)
The system makes use of two variables which you can easily modify in the script itself. You get to write on a game variable (one actual game variable) the info you want to pass. It can be anything! If you want to keep the Undertale idea as an example, it could contain a value 0-100 on your alignment in the previous savefile. Once you proceed to play a New Game, the game will read the variable from the latest savefile you have in the folder and will store it into another variable.
This way you can make a game "remember" some previous data. Of course with a little editing it's possible to pass more informations (i.e. more variables).
A suggestion on how to pass multiple boolean values through one single variable, though, is to use numbers that are power of 2 which is a quite useful method.