I'll take a cue from Samsara's Shin Megami Tensei "game end glitch" submission to say at the outset that I have no real idea how this run works.
Game objectives
- Emulator used: Bizhawk 2.9.1
- any% (Neutral ending)
- Manipulates starting RNG for very specific encounters and outcomes.
- Then manipulates memory via (I think?!) inventory-based glitches to ultimately trigger the Neutral ending.
Basic route breakdown
Create a save file
A save file is necessary for the RNG manipulation, so the first task is to save and then reset.
Manipulate RNG by starting the game on a specific frame
The RNG value is stored at address 0x7E03FA, and needs to be 72 (decimal) for optimum routing.
Specific routing, encounters, and movements
What follows is a series of extremely specific encounters and movement patterns. Once the demon Empusa is acquired on the bridge, everything is ready to go.
Preparing for the memory manipulation
The inventory is first set up in a specific way. Then Empusa casts warp in Disco. Some more specific encounter manipulations, healing, reducing magnetite to 0, and removing all demons except Cerberus. Now we're ready to execute the memory manipulation, after a save and reset.
Executing the memory manipulation
We cast Mapper and then get Cerberus's health to 441. Hiroko also needs a specific MP value. The Spartan demon is summoned into slot 1. The heal cost (279) is shown for Hiroko and Cerberus. Now we walk around until Spartan dies, triggering some glitchy goodness. We access a "RAM checker" (a debug menu) and set some specific flags. Warp, exit, enter the left entrance of the building, and exit. Voila, lengthy ending sequence triggered.
Other comments
I take no credit for the routing (well, other than a couple of minor improvements over the RTA) nor the manipulations that lead to the glitches. Hopefully someone with a deeper understanding of the game has some explanations?!