Does MS have an IP that on level with Gears or Halo that we don't know about?

[Goatseye]

I don't get the analogy of people getting "tired" of Halo. I really don't.
What FPS plays better or is a better saga than Halo? What's an alternative game with a better experience?
Or Gears series, which every TPS and their moms copy their game mechanics style?