This run uses very heavy RNG manipulation to get favorable outcomes, such as avoiding encounters entirely, and dealing with bosses at low levels.

A brief explanation of how the RNG works: When the game is soft reset by using Start+Select+A+B, it kicks you out of both games, back to the main title screen. This zeroes out every value in memory, except for a handful that are required for the title screen itself.

When FF1 is selected as the game, the RNG start running, at a rate of one increment per frame starting on the title screen, but pausing in menus (including the load menu) and in battle. Based on my personal mashing speed, I know I can get off of the title screen with between 0 and 12 frames lost.

Using that knowledge, and a giant spreadsheet of outcomes, I can accurately predict how to get the result I'm looking for either by selecting certain actions in battle, taking extra steps, or menu buffering. (Menu buffering advances the RNG by 1 count every time you go in and out of the menu).

The result of all this is that almost the entire run can be manipulated, save for a couple of small sections.