According to the European Union Intellectual Property Office, Square Enix has filed applications for “Shellshock” as well as “Guardian Codex.” The applications are filed under Class 9 for game software and Class 41 for online game software, with the former also being filed under Class 16 for strategy guides.
It’s worth mentioning that class 41 doesn’t necessarily mean that, if we’re talking about the new game, it will be online. The class is required for any kind of online feature, including smaller ones like leader boards and similar features.
While there has been no official statement from Square Enix regarding what “Shellshock” may be, Square Enix’s subsidiary Eidos Interactive published a game under the same name over a decade ago. Shellshock: Nam ’67 was a third-person shooter developed by Guerrilla Games. Shellshock released on PC, PlayStation 2, and the original Xbox in late 2004 and was later followed by 2009’s Shellshock 2: Blood Trails.
Meanwhile, there is no mention to what “Guardian Codex” is. If you allow some speculation, it may be a sequel or follow up to Square Enix’s 2012 card game RPG Guardian Cross on mobile platforms. However, there is also the possibility that the mark can be connected to the “Shellshock” one.