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The Japanese and English official Twitter accounts for Azur Lane both shared an official teaser for Operation Siren. This signals the long-teased exploration mode will come soon to the mobile game in every region.
The Japanese account posted more details on the teaser. Operation Siren will be added permanently to Azur Lane. It will be separate from both the main story and limited events. It will have battles with an extremely high difficulty levels. While story-related stages only have enemies ranging from levels 60 to 95, this overall area will have stronger foes up that might appear at level 115. The challenge-specific bosses will be even stronger and appear at up to level 128.
As Operation Siren is intended to be endgame content, it is aimed at players who have reached a Commander Level of at least 60 and performed Cognitive Awakening on at least 12 shipgirls to raise their levels past 100. (As of December 14, 2020, the highest level a shipgirl can reach is level 120.)
A mandatory app update released for the Japanese client on December 10, 2020 to prepare all players for the major content update. A roadmap published in September 2020 specified that Operation Siren should be implemented by December 2020. The upcoming update that actually puts the new game mode in motion will also improve the skills of several existing shipgirls, such as USS South Dakota and IJN Takao.
Yostar previously held a limited collaboration event with Dead or Alive Xtreme: Venus Vacation, which ended on December 10, 2020. The next event will be revealed at the Japanese annual Christmas livestream on December 21, 2020.
Azur Lane is immediately available worldwide on Android and iOS mobile devices.
