Revelations: Persona is the first game in the Persona series, which is a spin-off from the Shin Megami Tensei series, and was first published by Atlus for the PlayStation in 1996. It was actually the first game in the entire Megami Tensei series to be officially released in the West.
Shin Megami Tensei If… is a spin-off from the main Shin Megami Tensei series that is smaller and more confined than previous games. It was developed and published by Atlus in 1994.
This time the story is set in a school where a bullied pupil tries to summon demons in the gym, to deal with his harassers, only to wind-up being possessed by them and threatening to destroy the world. You play a group of schoolkids who team-up to try to stop him.
Shin Megami Tensei II is the direct sequel to Shin Megami Tensei and was first published in Japan in 1994 by Atlus.
While the basic gameplay is essentially the same as before, with tile-based movement and first-person combat sections, overhead city map sections, and magic, occult and religious themes, the developers deliberately chose not to connect this sequel directly to its predecessor, so story-wise it is somewhat different, being set in the far-flung future.
This cult Japanese Role Playing Game was originally released for the Super Nintendo in 1992 in Japan. It was developed by Atlus and is the third game in the Megami Tensei series, and the first in the central Shin Megami Tensei series.
The game mixes elements of philosophy, occultism, science fiction, religion, and role-playing in a somewhat unique way. It remained untranslated into English for a decade, because of its controversial content and Nintendo‘s strict policy guidelines. It wasn’t until 2002, and an unofficial fan translation patch by team Aeon Genesis, that the original SNES release received an English translation. An official English translation was eventually released on iOS in 2014 by Atlus.
The second game in the Megami Tensei series was developed by Atlus and published for the Nintendo Famicom by Namco in 1990. It’s another Japan-only RPG featuring demon-summoning and turn-based combat and is considered by many to be much better than the first game.
This is the very first Megami Tensei game, released for the Nintendo Famicom in 1987, and it looks very basic compared to later Megami Tensei games, but was the foundation on which a successful series was built.
Based on a trilogy of fantasy novels by Japanese author Aya Nishitani, Megami Tensei was originally created as TWO distinct role-playing games. One version (this game) was developed by Atlus and published by Namco in 1987 for the Famicom. A separate version for home computers was co-developed by Atlus and Telenet Japan and published by Telenet Japan the same year.
The original game was never officially released in the West due to its use of religious themes, and Nintendo‘s sensitivity to them, but an English fan translation does exist that can be applied as a ROM hack.