Core Decay is an upcoming indie first-person action role-playing video game developed by Ivar Hill and Slipgate Ironworks, and published by 3D Realms.

The player can interact with NPCs, collect logs and messages, hack computer systems, and engage in combat with enemies.

Ivar Hill created Core Decay as a personal side project while working as a professional game developer.

As a one-man team, he could not achieve the depth of such AAA titles, but could borrow many elements of those games such as emergent gameplay styles.

The game was developed simultaneously for both PC and mobile platforms, with only control schemes changing between versions.