The history of this engine deserves a specific mention. One day two guys wanted to make their own video game, but the tools available at the time did not suit them. They decided to create their own game engine and then work on it. After they finished their work, the guys decided that they were more interested in making engines.
Unity 3D is the most popular game engine among indie developers. It's hard to master, but there is plenty of guides, documentation, and video tutorials to help in this. The primary programming language is C#, but the available functionality allows you to create prototypes without writing a single code line. The built-in Assets Store contains tens of thousands of free and paid models, shaders, and other ready-to-use resources, saving you time.
Unity's versatility is also its biggest problem. If you need to do something non-trivial, be ready to rewrite the engine for the project's purposes.
Games made with Unity 3D: The Forest, Gwent, Escape from Tarkov, Ori and the Blind Forest.