Ultimate bosses are enemies that appear as completely optional bosses with powerful capabilities. What sets them apart from other optional bosses are the fact that they are the strongest enemies in the games they appear in, often requiring amazing levels of power and extensive strategies to defeat.
Ultimate bosses are typically hidden, have certain conditions, and are always in the end game, if not during a second cycle or new game plus. Some even require that several other optional bosses be defeated first in order to reach them.
Ultimate boss characters
Shin Megami Tensei I & II
- Beelzebub (Neutral and Law route in I & II)
Shin Megami Tensei: 20XX Devil's Colosseum
Shin Megami Tensei: if... Hazama's Chapter
- Lucifer (Refused Light Ring, defeated both Beelzebub, Baphomet and the Demon God Emperor and refused to forgive him)
Shin Megami Tensei III: Nocturne
- Lucifer (True Demon Ending's last boss)
Shin Megami Tensei: Strange Journey / Redux
- Demiurge (New Game + only, Alilat must be defeated and the final Enemy Search must be acquired prior)
- Belial, Nebiros, Lucifuge, and Beelzebub (Fought separately in a Redux New Game + only; must be on one of the new endings)
Shin Megami Tensei IV
- Masakado's Shadow (DLC)
Shin Megami Tensei IV Apocalypse
Majin Tensei II: Spiral Nemesis
- Angra Mainyu (Neutral Route)
Shin Megami Tensei: Devil Summoner
- Nanto Seikun and Hokuto Seikun (Must trigger the event flag by being right front of the door leading to Inaruna's burial chamber)
- Enoch, David, Leviathan and Squall (PSP version only; must have finished the game, and defeated Nanto Seikun and Hokuto Seikun; the four can be as an entire group during a New Game+)
Devil Summoner: Soul Hackers
- Devil Summoner protagonist (PlayStation and 3DS version only and only in the EX Dungeon after finishing the game)
- Raidou Kuzunoha the XIV and Raido Kuzunoha the XIV (3DS version only and only in the EX Dungeon after finishing the game and after defeating the protagonist of Devil Summoner)
- Soulless God Oumagatsu (3DS version only in the EX Dungeon. Must beat Raidou and Raido before facing him).
Devil Summoner: Raidou Kuzunoha vs. The Soulless Army
- Beelzebub (Reach the last floor of the training hall)
Devil Summoner 2: Raidou Kuzunoha vs. King Abaddon
- Masakado (New Game +, neutral alignment, and 99% completion of Case Files)
- Lucifer (New Game + and Chaos alignment last playthrough)
Persona 2: Eternal Punishment
- Philemon (EX Dungeon only)
Persona 3 / FES / Portable
- Elizabeth (2nd cycle*. Must accept her request and reach the top of Monad.)
- Theodore (P3P only, optionally replaces Elizabeth when playing as the female protagonist.)
- Margaret (P3P only, must have spared Ryoji Mochizuki on December 31 and completed all challenges in the Vision Quest.)
Persona 4 / Golden
- Margaret (2nd cycle only, Empress Social Link must be maxed, and all optional bosses must have been defeated after rescuing someone)
Persona 4 Arena
- Elizabeth (last foe of Score Attack)
Persona Q: Shadow of the Labyrinth
- Elizabeth, Margaret and Theodore (2nd+ cycle, must complete the game on both the P3 hero's and P4 hero's routes)
Persona 5
- Caroline and Justine (2nd cycle only)
Digital Devil Saga: Avatar Tuner
- Demi-fiend (2nd cycle only, reach the end of the Karma Temple and return to the Anahata basement before fighting the final boss)
Digital Devil Saga: Avatar Tuner 2
- Satan (Hard difficulty only)
Devil Survivor
- Lucifer (New Game + only, on any non-Yuzu route)
Devil Survivor 2
- Alice (with Nebiros and Belial, the two having been defeated prior)
- Tico Duo (Record Breaker only, must acquire the right to fight them while starting a new game, which will cause a special event to appear on Friday at 19:00 on the Triangulum arc only)