We first mentioned Hyper Defence XT when it first hit the beta stages. The Windows Phone game has now hit the open Marketplace and our first impressions hold true.

Not much has changed with Hyper Defence XT since we last visited the pre-release version.  The tower defense game is set in the fictional Outpost 26 where you have to defend the outpost from invading aliens. There are a wide assortment of weapons to buy and upgrade to wipe out the invading hords.

Continued after the break.

The game includes fifteen levels of play and an unlockable Survival Mode that throws everything but the kitchen sink at you. As you take out the aliens, you can earn hyper energy (the little lightning bolt squares) that can be used to give your weapons a boost of power during the stronger waves.

Each level requires you to survive at least twenty waves of attacks. You have ten "lives" for each level and if you let an alien survive its way past your defenses, you loose a life.

Game play is fast paced, challenging and ran smoothly. As with any tower defense game, weapons placement is key to your success and Hyper Defence XT is no different. It is equally important to upgrade your weapons to allow you to dispatch enemies with more speed.

Again, overall impressions remain high for Hyper Defence XT. Some tower defense games drag along as the enemy troops drudge along or in between attack waves. Hyper Defence XT moves along at a quick pace that keeps the game challenging and interesting. 

If you are a tower defense fan, Hyper Defence XT is worth checking out. There is a free trial version of Hyper Defence XT available with the full version running $1.29. You can download Hyper Defence XT here (opens Zune) at the Marketplace.