Touhou 15: Kanjuden - Legacy of Lunatic Kingdom

Someone's causing havoc in the Lunar Capital, and as a result, Lunarians are descending to Gensokyo in order to purify it so that it can be suitable for them to live there. With two problems to conquer, our girls set out to stop the Lunarian invasion - which also concerns Reisen, who also goes to investigate - and find the perpetrator behind the incident.