If you're a gamer and want an Android emulator, we recommend NoX. Everything about NoX has gamers in mind. From the speed, performance, smooth UI, to all the customization and controller support.
You can simulate gestures and on-screen navigation controls on a keyboard with ease. Assign your arrow keys to certain things like swiping left, right, up, or down. They offer controller support, joysticks work, and much more. NoX offers plenty of add-ons too.
As you expected, this is completely free. Try NoX Player.