Kingdom Hearts 3 development has switched over to Unreal Engine 4 engine, according to creator Tetsuya Nomura.
In an interview with Famitsu, Nomura said that the team switched Kingdom Hearts 3 over to Unreal Engine 4 for "various reasons" and that the development schedule is unaffected despite the change..
Nomura adds that because of the change, the team is having some rendering issues, and Epic Games is working closely with them to help resolve them.
The decision is a very a interesting and very odd one. Square-Enix has been working on its next-gen Luminous Engine for a while now, tech demos look incredible, so the switch to Unreal Engine 4 instead of the in-house option may be telling of how Luminous is coming along.