In the most basic terms Mirage: Arcane Warfare is a spiritual successor to Chivalry: Medieval Warfare. The big difference, as you can probably imagine from the name alone, is that Mirage features a far greater focus on spellcasting and unique character abilities over random screaming and weapon twirling.
If you're wondering what all of this might look like in action, wonder no more as the developers have released a rather lengthy gameplay preview showcasing all of the classes in action. Just do keep in mind that the footage you're watching is from an alpha build, so things are hopefully going to become much smoother once we get to release. Anyway, here's the video:
The Closed Beta will begin at the end of March, so if this video has piqued your interest make sure to go to the official website and sign up. There's no guarantee you'll get in with the first few waves of invites, but chances are you will get in eventually as the Closed Alpha had quite a few keys sent out. On the other hand, if you want to guarantee access to the beta you can also pre-order Mirage at $30 price tag. However, I'd still recommend holding off and giving it a try first as the Chivalry style of combat is really not for everyone. Good luck with the beta keys!