Immaterial and Missing Power

Immaterial and Missing Power is a two-dimensional fighting game in which players can select one of several Touhou characters to fight either against an AI, or other human players. Because of Touhou's origins as a bullet hell game, Immaterial and Missing Power's special moves have a focus on large amounts of projectiles. To help counter the large number of enemy projectiles, Immaterial and Missing Power, allows the player to 'graze' enemy projectiles, which gets its namesake from the prior Touhou games. While in the bullet hell Touhou games, grazing refers to having enemy projectiles collide with the player's sprite, but not their hitbox (which is several times smaller), in Immaterial and Missing Power, the player can use an energy meter to completely circumvent enemy projectiles, though not all projectiles can be grazed.

Spell Cards, a central aspect of Touhou since Embodiment of Scarlet Devil, appear in Immaterial and Missing Power as special moves that have to be announced before they can be used. Each character can choose 1 out of 3 normal spell cards, and 1 out of 3 overdrive spell cards to use before a match starts. The overdrive spell card replaces the normal spell card when the player's character has been defeated once. Also, when a spell card is announced, the player's HP replenishes for a certain amount.

During Gensokyo's summer, there occurred an incident called the Night Parade of Ten Thousand Demons Every Four Days (三日置きの百鬼夜行). In this incident, the sakura trees have since shed their blossoms, but the hanami kept on going, with feasts being hosted day after day with no end in sight. Additionally, each time the feast is held, an unknown restless spiritual aura in Gensokyo also increases, but this spiritual aura itself had no effect, leading to suspicions of those who went to investigate it. As such, everyone who goes to the feast, be it human or yōkai, appear to be very suspicious. Three days before the next feast, the player character sets out, each on their own, and attempt to investigate.

Unabara Iruka (海原海豚) of the Twilight Frontier team had wanted to make a fighting game with aerial battles similar to Cyberbots: Full Metal Madness (1995) and Astra Superstars (1998), but felt that creating a whole set of characters and the setting just for the game would be overwhelming. Unabara felt that such a game would not feel out of place in the setting of Touhou, and so he sought out ZUN, the founder of the series, to collaborate on a Touhou fighting game.

Unlike the main Touhou games, which were written developed entirely by ZUN, the dialogue, character sprites, and ending artwork in Immaterial and Missing Power are drawn by alphes, an artist at Twilight Frontier. ZUN was responsible for character design, the plot, stage design, system graphics, Spell Card naming, and a portion of the soundtrack while Twilight Frontier took care of the rest.