I imagine it was very difficult to get all the relevant parties to agree to this.
Source: http://gematsu.com/2017/04/sinoalic...aboration-event-announced#33e6clc72zQu4rlu.99SINoALICE, Square Enixs upcoming smartphone game led by Yoko Taro, will have an in-game collaboration event with the PlayStation 4 and PC action RPG NieR: Automata, the company announced.
The collaboration event consists of a quest with a dedicated special scenario written by Yoko Taroa story surrounding the amusement park boss Beauvoir. In this quest, music from NieR: Automata will play, and NieR: Automata characters 2B, 9S, A2, and Emil will appear in addition to NieR: Automata weapons and original Weapon Stories.
SINoAlice is due out as a free-to-play title with in-app item purchases this spring in Japan.
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