Nintendo could be preparing to spring a big surprise on us with the allegedly imminent release of Project Giant Robot, a Wii U game shown only in prototype form at E3 last year by the legendary Shigeru Miyamoto.

We've heard nothing of the game since last year's event but an earnings release from Nintendo for the financial year ending March 2015 lists the game for a release in the first half of 2015. The earnings report was made available to public recently and can be read here.

The report lists it for release in 2015 in Japan and the United States but specifies a release in the "first half" of 2015 when it comes to the European release. This may be a slip up, or it could mean Nintendo are preparing to pop the game in as a surprise during E3 next month.

Project Giant Robot tasked players with building and then piloting a giant robot that would then do battle with another robot in a cityscape environment. It was a basic gameplay demo and most definitely just a prototype, but it did show promise.

The game was shown off alongside another prototype, Project Guard, which also made use of the Wii U's gamepad, putting players in control of a series of sentries they must switch between to defend a base.

Nintendo's report also lists that for a release in 2015, though nothing more specific than that.

Nintendo have yet to announce details of their E3 plans, but it is expected they will air a Nintendo Direct broadcast as they did last year, then a live-streamed treehouse event from Los Angeles featuring all the games they decide to show off.

E3 runs during the week commencing 15 June.