C2 Architecture reboots Plan-[ki] as a Strategy RPG for PC and Mobile

C2 Architecture has revealed that they have been resuming development for Plan-[ki]. The long-dormant project is now being worked on as a strategy RPG that will be available for PC and mobile. Note that even though the studio published this on April 1st, this announcement is considered legit as they posted it after noon in Japan's time zone.

Plan-[ki] was initially revealed in April 2011 as a game that would fuse visual novel and strategy genres for PCs with Windows XP, Vista, and 7. C2 Architecture originally planned to release it within 2011, but they ended up putting it on hold as they were busy with the game they have become best known for: Kantai Collection, also known as KanColle.

The studio last updated this webpage in 2019, where they tried to restart development for Plan-[ki], but there were no further major updates until today's announcement. As another fun fact, the character designers in this project—Konishi and Shibafu—are also well known for having designed numerous shipgirls in KanColle.

You can find the original announcement tweet in Japanese right below, followed by our English translation of the text:

C2機関が「艦これ」前に企画していて、「艦これ」のまさかの爆発で開発が止まっていた【#キ号計画】。

多くの仲間も参加して、現在開発が進んでいます！
PC&モバイル #SRPG #歴史SF作品 のC2機関「キ号計画」。もう少しすると何か色々見えてくるかも!?
メインキャラデは、コニシ隊員&しばふ隊員！… https://t.co/Dio9dWSSQ3 pic.twitter.com/fN6CxXeaTm

— C2機関 (@C2_STAFF) April 1, 2026

C2 Architecture made the Plan-[ki] project before KanColle, but [the former's] development was stopped due to KanColle's unexpected boom.

Right now we are progressing on [the former's] development, with many friends also joining us!
C2 Architecture's #SRPG #HistoricalScienceFictionWork Plan-[ki] for PC and Mobile. We might be able to see quite a lot of things in just a bit more!?
The main characters' designs are being done by Konishi and Shibafu!

A new system that will have communication as its core.
Although it takes place in an Alternate Showa era, it will also have mechs! Here's a few playable screenshots from the development build.
We're unexpectedly going All 3D here!
We're also doing this in secret... Look forward to it, no matter how little!