A new version of the id Software engine-derived open source shooter Alien Arena has been released, bringing this action title to version 7.20 and adding a slew of new features:

Version 7.20 features a host of improvements, optimizations, and new features such as the implementation of per-pixel GLSL effects including parallax, normal and specular mapping/highliting, occulusion culling of entities, shader performance boosts, new and improved weapon/event effects, and much more. The end result is a game that not only looks great, but also runs considerably faster than previous releases.

On the gameplay aspect, a brand new reward system has been implemented, allowing players to choose from three powerups when reaching a certain achievement total. Weapons have received further balancing, powerup effects made more smooth, and various bugs have been squashed. Several brand new levels have been added, as well as player skins that improve visibility and an HUD based weapon inventory.

You can nab it for Windows and Linux right now from AusGamers. The official site has a couple of new screenshots showing off some of the new visual effects.