On August 31, 2025 Blue Archive was hacked, which caused a massive amount of Koyuki (and, in some cases, either Hatsune Miku or every single student that was released, including alternate and crossover character) chibis to spawn in the player's cafe. Some banner pickups and events were also replaced by pictures of Koyuki.
The game was subsequently taken down for maintenance, as memes started spreading about the incident.
The incident only seemed to have affected the Korean and Global versions; there are no reports of it having occured on the Japanese and Chinese versions. Despite this, users in Japan still got wind of the event through other channels with some "joining in the fun," so to speak.
August 31 also happened to be Suzumi’s birthday. As one of the most overlooked students, a few fans pitied her as well. It was also the birthday of both Hatsune Miku (hence, her inclusion in the hack) and the game's production director, Kim Young-ha.
