Sword fusion

Sword Fusion is a system in certain games in which a demon can be fused into a blade (or another weapon) to enhance its properties.

Appearances

 * Shin Megami Tensei
 * Shin Megami Tensei II
 * Shin Megami Tensei: Devil Summoner
 * Devil Summoner: Soul Hackers
 * Devil Summoner: Raidou Kuzunoha vs. The Soulless Army
 * Devil Summoner: Raidou Kuzunoha vs. King Abaddon

Devil Summoner: Soul Hackers
Sword Fusion can be performed at the Hotel Goumaden with Muramasa. This process sacrifices a demon to be fused into the Nameless Sword, changing its properties. The sword's Attack depends on the demon's level and strength, and the swords' Hit depends on the demon's level, agility and luck. In some cases, a special weapon is created when certain demons are fused into the blade.

Devil Summoner: Raidou Kuzunoha vs. The Soulless Army
Sword Fusion can be done at the Gomuaden with Victor. Like other fusion in the game it requires the demon to have Max loyalty. Unlike Soul Hackers fusing a demon with your sword just boosts its power as well as giving you resistance to a damage type and a boost to one of your stats. However, fusing the demons Nagasunehiko, Abihiko, Hitokotonusi and Mishaguji to the same sword, in any order, separately or together, changes the blade permanently to the Onmyo katana class, the most powerful blade in the game.

Devil Summoner: Raidou Kuzunoha vs. King Abaddon
Victor's Ippon-Datara informs Raidou during the story of his master's new type of fusion: rather than directly fusing a demon with the sword, Victor now can combine various types of enemy-dropped crystals with Renki swords to create weapons of various kinds, allowing for flexibility in the use of swords to suit more kinds of gameplay.

Sword Fusion is used to make the Youmetsutou, a sword that can harm Apollyons.