16 save files - one for each combination of bosses killed. In each save, all plates are unlocked, but no fertile grounds are healed.

Just by looking at the saves from the main menu, it can be difficult to know which save represents which combo. As such, they are ordered in a way to help you locate the correct save. Here are two ways to find out which save to load:

1. When you download the saves, there will be a key.txt file. This file tells you which boss combo each index represents, e.g. save number 7 is where Alchemist, Concubine, and Warrior are killed (but not Hunter). So from the main menu simply count 7 saves down (starting from 0) and load that save.

2. (Better way; looks hard but it's easy) Picture the four bosses on the map, going from left to right - i.e. Hunter, Alchemist, Concubine, Warrior. Represent each boss's status with a bit - i.e. 0 means the boss hasn't been killed, and 1 means the boss has been killed.

Then a 4-digit binary number can represent every possible combination of bosses killed. E.g. 0000 means none of the bosses have been killed; 1010 means Hunter and Concubine have been killed; 0111 means Alchemist, Concubine, and Warrior have been killed; 1111 means all bosses have been killed. Finally, convert this number to base-10, and that is your 0-based save index.

EXAMPLE:

Suppose I want to test doing the Hunter fight with longfall, and then go to Mental Realm from there. To get longfall, I need to do Alkara glitch during the Concubine fight. So I need a save where all bosses except Hunter and Concubine have been killed - i.e. Alchemist and Warrior have been killed. This is represented by the number 0101, which is 5 in denary. Therefore I should load the 6th save from the main menu (or 5th if counting from 0).