Save files at all of the following locations:

Dark Ruins - Ten Block Puzzle

Dark Ruins - Lever Puzzle

Dunes - Minecart 1 and 2

Dunes - Sandstorm

Snowdin - Trap Bridge

Snowdin - Rolling Rock 2

Steamworks - Generator Left

Steamworks - Generator Right

Steamworks - Steam Vents 1, 2 and 3

Pacifist Martlet

Pacifist Dalv

Pacifist North Star

Pacifist Guardener

Pacifist AXIS

Pacifist Ceroba

Flowey

Genocide Dalv

Genocide Martlet

Genocide Ceroba

Genocide AXIS

Genocide Zenith Martlet

[CHECK YOUR DIMENSIONAL BOX WHEN YOU LOAD INTO BOSS FILES]