❶ Map
The map of the game is open, creating a realistic viewpoint of the utopia for the player.
Having basically 2D horizontal map, the game seems like a horizontal runner game at the first glance. However, there are two elements which give the game the feel of a 3D open world based on multiple pieces of 2D maps.
Layers of Map
Having multiple layers in the background moving according to the perspective of the camera give user a sense of depth. The background maps maybe blurred to offer also a sense of depth.
Freedom of Map
The multiple background maps are actually different "streets" of the world meaning that the users are virtually capable of accessing those maps when entering the connection. Also, the buildings in the maps are separated small maps and are thus accessible. I also think that enable the user to climb up the buildings can offer more pleasure.
Though a 2D horizontal adventure at the first glance, it is a open world RPG at its heart, having the mission system, side stories, and NPCs wandering around providing users with incredible freedom of behavior.

❷ Story
The discussion of the the story only has meanings when we consider the standalone aspect of the game. Now, I imagine the story to be of a neophyte in the utopia, growing up to become a master of the land. The story is about meeting people, learning skills, and advance spells. The character you foster in the story will be the one you use in the online version.

❸ Character
You will be allowed to foster a lovely character of you own by yourself as you advance in the story mode.

❹ Spells
As a game based on the worldview of the Touhou Project, the ability to create the spells is at the heart of this game. The user can select the appearance of the particles, pattern of the particle clusters, sequence and position of the bursts of the particles, action of spates of the particles after they are spawned, and the effects and sounds of the whole process.