[daemin]

There's Lumberyard which you could say is a fork of CryEngine. But in general I don't see studios lining up to use either of the two.

Also the idTech engine is limited to games that are published by Bethesda. So you can count it as an in-house engine now, just like Frostbite is for EA.

[georgeecollins]

Lumberyard really doesn't have the support that Unity and Unreal have. It is hard to recommend using Lumberyard when there are alternatives that are well tested, well documented, and many developers are familiar with.