An introduction to Warsow, from its homepage:

Standalone game for Windows and Linux
3D Engine based on Qfusion (a modification of Quake 2 GPL engine)
eSport oriented FPS
Fast-paced gameplay focused on trix (trick jumps) and art of move
Complete Power-up System including Weak and Strong fire mode for each weapon
Cartoonish graphics with celshading-like_but_not_Manga style, mixing dark, flashy and dirty textures, matching with action full of fun and speed
References : Quakeworld, Quake3 CPMA, Jet Set Radio, Speedball.

Let's do the motions, shall we? Also, warning, lots of colloquial FPS terms down in the review, so try and keep up as best you can.

Graphics and interface. Rather than take the route every contemporary shooter has taken and beefed up the graphics and using it as a selling point, Warsow instead went the way of the WoW and used a stylized, cel-shaded approach to the graphics. This route lends its own brand of charm to the game since it drastically lowers the requirements needed to play it, plus you don't have to mess with the console to get "optimized" (ultra-picmipped fugly mode) graphics, since it's blazing fast out of the box. The effects aren't distracting, the weapons and powerups have brightskins by default and can be identified even from a distance, and nothing detracts takes your focus away from the battle at hand.

The interface, as you can see here, is simple and effective. Health, armor, weapon layout with strong/weak ammo count, and scores. Really, what more do you need? No more interface hacking like you have to do with the current Quake III Promode mod. No clutter. Again, nothing detracting from the battle - the interface just works, even in the midst of a hairy firefight.

Sounds and audio. This is where Warsow falls a little flat, but forgivable because it's still in early production (did I mention that the game isn't even version 1.0 yet?). But the basics are all there - weapon and item pickups, distinct weapon sounds, painsounds, jumping sounds. What I'd like to hear in future versions are the varying painsounds from CPMA and some decent footstep sounds - the latter being noticably absent and making it very difficult to position opponents. And thankfully, NO DROPPED SOUNDS (I'm looking at you, Q4).

Maps and models. The models are nothing special, just a male, female, and alien one with just one skin. That one skin is a Promode-type skin though, meaning that you can customize it with RGB sliders to the color that you want. Weapon models are very nice (with the exception of the strange-looking Gunblade), with distinct colors to differentiate them. The DM maps are kind of cluttered, but the midair maps are hella fun, which I'll get to in a sec.

Weapons. Ah, my favorite aspect of the game. Warsow's weapons layout is brutally simple: a melee weapon (Gunblade), a shotgun weapon (Riotgun), a plasma weapon (Plasmagun), and versions of the Quake favorites - a grenade launcher, a rocket launcher, a lightning gun (Lasergun), and yes, everyone's favorite railgun (Electrobolt). The Quake series has proven that a balanced set of standardized weapons makes for more skillful games and less weapon spam, and Warsow picks it up nicely. No alt-fire nonsense (sorry UT/CS), but what Warsow does to mix it up are two separate sets of ammo, "strong" and "weak." Strong makes a weapon behave like it normally does. The lightning gun is a perfect hitscan beam, the Electrobolt is an instantaneous shot, etc. etc. Once you run out of strong ammo, however, each weapon reverts to its weaker counterpart - the gunblade becomes a strictly melee weapon (it has ammo to begin with), the lightning gun has a huge tracking delay (the beam bends as you swing it around), and the railgun instead becomes a projectile weapon that has travel time. This lends a great element to map control as you can deny strong ammo from your opponent, reducing his or her effectivity, and more or less ensures weapon spam is kept to a minimum.

Weapon switching is also very fast (but not as fast as Quakeworld/CPMA), which leads to limitless possibilities of weapon combinations. Fragging with the EB after launching your opponent into the air with the RL, or finishing of with the LG after a volley of rockets never gets old, after all.

Movement. Movement is one of Warsow's primary features, and whose defining element revolves around the "action button." From the Warsow website:

Beside classical trix coming from quake scene, like Circle Jump, Strafe Jump, Double Jump, Bunny Hopping, War§ow features its own Special Moves :

Wall jump
Using walls for powerful rebounds
Press Special Key when touching a wall during a jump

Dash
Allowing quick accelerations on the ground
Simply press Special Key when on the ground

Dodge
Allowing quick and powerful sidesteps
Press Special Key + Any Strafe when landing on the ground

Ramp Slide
Allowing unlimited Dash on ramps
Press Special Key when running along any ramp

Dash Double Jump
Allowing double jumps on low edges
Press Special Key then quickly press Jump when running onto any low edge on the ground

As you can see, the Special Key adds a fantastic element to the already fast movement. But breaking it down, the speed and action is sort of a balance between Quakeworld and CPMA - a fair amount of air control, proper circle/strafe jumping is rewarded with blazing speeds, and even double/ramp jumping is possible thanks to the Special Key. Everything I love about CPM physics is well-represented, and flying across WDM1 is as satisfying as tricking ever was in Q3A.

Gameplay modes. Standard Quake modes are present, i.e. CTF, TDM, DM, and Duel, along with cult Quake favorites like midair (frags are awarded only for kills made while your opponent is airborne) and instagib (rail-only, one-shot kills) for those times when you just want to go nuts with your friends. There's a limited but satisfactory number of maps for each mode, and are more than enough to have quick pickup games.

Netcode. I actually just finished an online instagib match, and after a commanding lead by my opponent I caught up and got 15 frags on him by the time the buzzer hit. All this on 200-500 ping which is generally unplayable on a fast-paced FPS, especially Warsow. But lo and behold, I was hitting my rails consistently (my weakest weapon, but for some reason I do better when I'm lagged the fuck out). I don't know if it's because the netcode is fantastic and on the level of CPMA, or because I was just lucky, but I have to concede that online play is definitely possible with a decent connection.

Software and packaging. There's a catch with installing Warsow - there is no installation! You just download the 65MB zip from the Warsow homepage, extract the contents into a folder of your choice, and launch warsow.exe. Boom! You're in the game. Just configure your controls and settings using the self-explanatory and easy-to-use menu, and you're on your way to deathmatch fun. And even better, since it's a self-contained program, you can even keep it on a USB drive and play anywhere you can play Quake II - which is umm, everywhere? If a PC can run DotA, it can certainly run this.