The game comes on 2 CD-ROMs and installs easily, as you'd expect. There's already been an update to version 1.0.9.6 that you should definitely apply before playing, since it fixes a couple of nasty bugs. The update can be found at http://www.macgamefiles.com/detail.php?item=17789.

Setup
Keyboard setup is easy and is divided into 4 sections: Global, Marine, Predator and Alien. This simplifies switching from one character to another without having to rebind all the keys, because each race or character has a few unique abilities and functions. The global settings apply to all 3 races, while the special settings only set the functions that are unique to each race. This comes very handy and is a big plus in favor of the setup menu. The drawback is, that certain keys cannot be used, because they are not recognized by the game, however this didn't turn out to be a real problem. Otherwise the setup menu offers a lot of options on adjusting graphics detail and resolutions, however, turning down the graphics won't affect performance significantly, according to some angry gamers talking about performance issues elsewhere on the net. But I'll get to that later in my review.

Character Overview
Upon starting a singleplayer game, you get to choose between the 3 different races that you can play: Marine, Predator or Alien.
Each race has a different storyline to play through, however they're all connected to each other one way or the other and you'll often find yourself recognize a scene that you have already played in a different character and from a different viewpoint. This interweaving of the 3 storylines into one global plot is clearly one of the strengths of this game. However it is sensible to educate yourself a bit about the Aliens and the Predator movie series first, in order to understand all the details. (There are 4 Aliens movies and 2 Predator)

Gameplay
Aliens vs. Predator II is, just like its predecessor, a game that relies heavily upon the build-up of tension and fear and it succeeds very well at that, although it is not as frightening as the first part was.

However playing the Marine part is still a true challenge for your nerves, as you run through dark corridors and strange alien structures, not knowing where to turn next. Your motion tracker pulses monotonously, just to send cold shivers down your spine as soon as it starts beeping in that classical aliens-style sound, indicating motion in front of you. Sometimes it's just a moving door or a little insect, sometimes it's certain death waiting for the unprepared. Also, aliens have the unpleasant habit of attacking in groups, from all sides, including from behind, where your motion detector will not warn you. Be prepared to almost fall off your chair in fright a few times. It's most fun playing in the dark and with headphones:P Having played the game at "Normal" difficulty, I consider the Marine part to be the hardest of the three.

The Predator, as the name says, is the hunter kind of character. With a massive arsenal of intelligent and stealthy weapons, the ability to cloak and jump very high, you'll mostly find yourself attacking unsuspecting enemies from behind or - thanks to zoom mode - from a far distance. Unlike the Marine, which has to pick up armor and health, as it becomes available, the Predator has a Medicomp and an Energy Sift Device to supply it with an infinite amount of energy for weapons and health...if you find the time to charge up, before being detected and killed. Uncloaked, the Predator is fairly weak and you'll have a hard time dealing with enemies that can see you.

As an Alien, you start off as a weak little facehugger, trying to find a host. Once you have found one, the facehugger will morph into a chestburster, which is even weaker. Both states require the player to use stealth instead of force, which might turn out to be quite challenging to those who prefer the common brute-force approach. After feeding and morphing once again, you'll have become a full grown alien, with all the capabilities we're used to from the movies. Armed with your claws, teeth and tail and capable of climbing up walls and ceilings, you will be able to explore the game from a completely new perspective. To regain lost health, you still have to "head-bite" you enemies, as seen in the first part already. It's up to you to decide whether you prefer fast and furious combat, or sneaky stealth strikes. The Alien part is clearly the most interesting piece of the game, and also the most innovative.

Graphics
The graphics in Aliens vs. Predator II, while a considerable step up from Aliens vs. Predator, are, for today's standards, a bit dated already. Level design is well done, but the lack of geometrical detail prevents the alien environments to look really amazing. Texture detail, while ok, is also far from the detail we can now observe with games such as Unreal Tournament 2003. The whole game is based on the Lithtech Engine from Monolith Software. According to the developers at Omni Group, AvP 2 pushes the fairly dated engine to it's limits, which is why both the graphics and performance are only mediocre.

= Screenshots =

Sound
One of the biggest strengths of Aliens vs. Predator 2 is the sounds and ambience. Sticking strickly to the sound set of the Aliens and Predator movies, you'll hear all the famous and familiar screams, door motivators and weapon sounds that we all love. That, paired with the situation adaptive background music really gives the game a movie-esque feeling, dramatically helping in the build-up of tension, giving it that typical "Aliens" feeling. This becomes particularly apparent when playing the Marine, which makes the best use of the noise palette in my opinion.

Performance
This brings me to THE one negative point of this game. Even though Omni worked hard to rewrite pieces of the code to make it run well on the Mac, the engine still has some bugs that definitely should have been eliminated.
First of all, the game tends to get slower and slower the longer you play, up to the point of being absolutely unplayable (and I mean unplayable as in "less than 1 frame per second", not 15), no matter how fast your machine is. The only remedy for this intolerable behavior is to quit and restart the game.
Aparently the problem is a memory issue and particularly people with little installed physical RAM will run into this problem much faster, than the ones with lots of RAM. Another problem occurs when switching vision modes (the predator has 4, the marine 2 or 3, depending on how you define it, and the alien has 2). While the nastiest bug with the secondary alien vision mode has been fixed in the patch to 1.0.9.6, there are still remaining issues with the nightvision mode of the marine not working properly, being too bright and not switching back properly to normal vision when turned on, and similar problems with the predators electrical view mode not displaying textures properly. While these are relatively minor issues, they do impact the enjoyability of the game quite a bit, which is a real pity. Last but not least, the game occasionally fails to quit and crashes, sometimes even the Finder, at least on my system running OS X 10.2.8 (the latest build).

Multiplayer
Aliens vs. Predator 2 comes with 6 default multiplayer modes:
Deathmatch, Team Deathmatch, Hunt, Survivor, Evac and Overrun.

While Deathmatch and Team Deathmatch shouldn't require any explanation, the other four modes probably need some explaining:

• Hunt is basically a tag-style game, where only the hunters can score. However when a prey manages to kill a hunter, they switch roles and the prey becomes hunter and vice versa. The player with the highest score at the end of the timelimit wins.
  
  
• In Survivor you start of in a normal tag mode, until the first people get killed, which turns them into Mutants. Survivors get points for each second they stay alive, while Mutants get scores for killing survivors. The guy with the highest score wins.
  
  
• Evac and Overrun are similar to "Escape" and "Assault" mode as we know it from Assault on Terror aka Tactical Ops, or Unreal Tournament. In Evac you have to get to the rescue zone within a given amount of time in order for your team to score, while in Overrun you have to assault the enemy base within a given amount of time.

All multiplayer modes offer a lot of options to configure settings, limits, weapons, players, available races etc. I imagine with the right people and the right settings on the server, multiplayer can be a great deal of fun.
There's also a special server application "AVPServ" that let's you host a dedicated server.

Summary
Aliens vs. Predator, despite all the issues it has, is a definite "must-have" for all fans of either movie series or the first-person shooter game genre.
It is clearly one of the most frightening titles currently available for the Mac.
If you have a slow machine and/or little RAM installed, you might want to upgrade first or wait until you have a faster machine. I'd certainly not recommend getting the game if you do not even match the minimum system requirements, which there are:

• Power PC G4 700MHz
• 256MB RAM (iMacs req. 512MB)
• Radeon 8500 or Geforce 2 MX with 32MB
• Mac OS X 10.2.5

as opposed to the G3 233MHz wrongly stated on MacPlay's AvP 2 website!

I've played it on:

• PowerMac G4 Dual 1250MHz MDD (2MB cache per chip)
• 1024MB RAM
• Radeon 9000 Pro
• Mac OS X 10.2.8

And it ran very well at 800x600x32 and high detail settings, apart from the abovementioned issues, that apparently can't really be resolved by a faster system.

Pros:

• Sound/Music
• Plot
• Atmosphere/Tension
• True to the movies (generally, not the story)
• Lots of options
• Fun multiplayer modes, also cross-platform
  
  Cons:
  
• Serious performance and graphics issues (v1.0.9.6)
• No Gold edition, thus rather short singleplayer experience
• Some keys can't be bound

MacPlay's website detailing Aliens vs. Predator II can be found here:
http://www.macplay.com/games/avp2.php. The game can also be ordered online.