Shin Megami Tensei II Gaiden: Ma To Houkai (真・女神転生II外伝 魔都崩壊?, lit. "True Goddess Reincarnation II Side Story: Demon Metropolitan Collapse") is a dungeon-crawler RPG. It was developed by Atlus and Bbmf for FOMA703i and 900i series mobile phones.
- Japan: June 18th, 2008
The setting is a virtual network game called Noah's Ark (ノアズ・アーク?). Dungeons are automatically generated so the structure changes upon each entry. By accessing treasure chests on each floor, players can acquire items to boost their abilities, restore their health, and do things like seal enemy demon movement. Combat is turn-based. Players can use weapons like swords for melee attacks, guns for ranged attacks, and magic for spell attacks. Series staples such as demon negotiation and demon fusion are also possible. Floors can be either regular, boss, or rest floors, where players can fuse or store items, but it is possible to use teleport stones to return to terminals at any time. When a player dies, they will lose all items and demons with them, but their level will be unchanged. In demon negotiation, demons can ask for any type of item, consumable, or bullets, as well as player HP, Magnetite, and Macca. Players can only summon one demon at a time, but can store up to ten in their COMP. Sword fusion is also possible as a means to acquire better swords. Players can strengthen guns, armor, and helmets in a similar manner.
Once players have cleared B100F, enemies become stronger and bosses more frequent. Players are contacted by the developer of Noah's Ark on B180F and the choice at the point will decide their ending. Those that agreed to cooperate with the developers of Noah's Ark fight against Lucifer at B200F. Those that did not cooperate with Noah's Ark will fight against Satan on this level.
After completing the game, it is possible to use the reincarnate function to challenge dungeons again with the same level and equipment the player finished the game with.