Microsoft's Halo: Spartan Assault game has been updated to version 1.1, adding 5 new mission and support for Windows Phone devices with 512MB RAM (Nokia Lumia 520, 620, 625, 720 and HTC 8S). The game, which was released for high end devices just over a month ago, is a top-down shooter, with cutting edge graphics and best-in-class audio.

The game is described as exploring the "first missions of the Spartan Ops program" and diving "deeper into the back story of Human-Covenant wars". Across a total of 30 missions players "see" though the eyes of either Commander Sarah Palmer or Spartan Davis, who are stationed aboard the UNSC Infinity.

Here's how Microsoft describe the 5 new missions:

In the new five-mission Operation Hydra expansion update, you intercept a haunting alien signal after the destruction of planet Draetheus V. Following the signal to the core of the planet’s moon, you discover its terrifying source—and a surprising new mystery to unravel.

Here's how we concluded our Halo: Spartan Assault review:

After many months, if not years, of waiting, Microsoft have delivered on the implicit promise in having the gaming section of Windows Phone branded Xbox. We now know the answer to the question 'will Halo come to Windows Phone?', and it's time to ask a bigger question. Is it any good?

The short answer is yes, it's good. It's bloody good. But there is room for improvement. The presentation, top down look, and slight 3D graphical look are all fine. The level design, small but perfect, works as well. I have a tiny issue with the control system, but it is easily played around. In that sense Halo works with no major compromises damaging the game.

The lack of multiplayer is slightly upsetting, but not a huge mis-step in the grand scheme. The inclusion of freemium to try and eke out a little more money from the gamers does feel wrong, for all the reasons above. Halo is a recognised name, and it does feel like this is cashing in as much as possible on the name for a short term success, rather than stopping and thinking about the long term impact.

I'm still giving Halo: Spartan Assault a 'mega' score of 90%, but it's with some caveats. Bring freemium is one of them. The second is a little note to say all the hard work is done in terms of infrastructure, gaming engines, and coding. I expect a sequel, or at least an additional level pack, before the end of the year. Halo: Spartan Assault better not be a one-off on Windows Phone.

Windows Phone Store description:

Halo: Spartan Assault brings the excitement of Halo combat to touch-based devices for the very first time. Battle your way through 25 action-packed missions against the Covenant as you explore the origin of the Spartan Ops program and Halo 4's Spartan Commander, Sarah Palmer.

It's time to join the assault, Spartan!

Halo: Spartan Assault can be downloaded from the Windows Phone Store. Unusually for an Xbox Live title there is no free trial. The game costs £5.49 / $6.99.