I think this is an opportune moment to mention that last year, I decided to give Irrational's back catalog a spin. Here's what I discovered.
Freedom Force
To sum this game up quickly, it began as gleeful fun which descended into frustrating keyboard-pounding after about five or six hours. It's an extraordinarily deep tactical RPG that starts off very slow an easy, with your small team of superheros beating up the bad guys and causing a ton of property damage along the way. The first couple of hours flew by, using telephone poles to knock buildings to their foundations to thwart evildoers raining bullets from rooftops. But as the game progressed, the learning curve went steep, and the difficulty curve skyrocketed. Missions began taking dozens of replays in order to complete, even with a liberal use of quicksave/load. Maybe I just didn't understand how to play the game or the game isn't for me, but I was legitimately enjoying myself up until the "nuclear winter" map and subsequent story about giant ants, at which point I put the game down, never to return. It's a shame too, because I really did like the game, and was excited at the prospect that there was so much game ahead of me. It's considerably long, doubled when you include the sequel. I suppose I could have tried it again setting the difficulty down to baby-style (I was playing on normal. Normal! Not hard.) but I had bigger fish to fry.
Tribes: Vengeance
This game is my best experience of the three. Were it made today, with the current attitude towards writing in games, it would sweep every award venue and leave Bioware and Rockstar's writing in the dust. Taking a cue from literature or cinema, unlike most games this one does not follow the part of a single protagonist on his or her journey. In fact, one could argue that there is no protagonist (nor antagonist), merely a character whom you happen to be playing at the moment. (For the record, I've always wanted to write a game like this.) The plot is told non-chronologically, jumping back and forth over the course of around twenty years, and from the point of view of five characters (two women, three men), one of whom you play at various stages of childhood and adulthood. The characters are all dramatically linked; you play mother and daughter, lovers, brothers, and a betrayer. Whole the storyline may be a bit melodramatic for some (it's a space opera, but with the scent of soap) but it's so different from the usual action game / rpg plot that I really didn't mind. Like the history video said, as complex as the plot is, it's not that difficult to follow, and provides a fascinating romp throughout. This was a game I was playing to find out what happened next.
But what about the game? For those unfamiliar with Tribes, it's a bit of Terra Nova (not just because of the melodramatic space opera plot) and a bit of Unreal Tournament 2004. There's a ton of variety in the mission offerings, though some felt genuinely like fillers to pad the game's length, or as tutorials for multi-player modes. With that in mind, the gameplay and level design ranged from completely awesome to frankly terrible. You have corridor-shooter maps, open ended exploration/quest maps (clearly the best parts of the game, and thankfully plentiful), sporting arena maps (the worst parts of the gamer, and sadly plentiful as well), and some rail-shooter/vehicle maps. If the training maps were skippable (they appear constantly throughout the game, even up into the last chapter) I would have enjoyed the title a great deal more. The difficulty is also very inconsistent, from cake-walks to replay-me-twenty-times tough. (Yes, even with quicksave.) Still, the parts that were fun were very fun (I especially enjoyed playing the assassin character) and kept me playing in spite of the awful parts, and in spite of the excellent plot.
Swat 4
In many ways Swat 4 is the polar opposite of Tribes Vengeance. There's no plot to speak of, and while both offer quite deep gameplay, Swat 4 is excruciatingly slow-paced (as a Thief fan, consider that deliciously slow-paced) tactical shooter with emphasis on re-playability in a handful of extremely small and detailed maps. You command a team of four swat officers which you can either micromanage meticulously (hint: on anything other than easy, you must micromanage them meticulously) or take point and allow them to merely follow your lead. There's a dizzying array of pre-mission customization options for your team as well. As I said before, the maps are very small, but the locations of the enemies and hostages (both mission-critical and otherwise) are randomized. You can't save during the missions, and often one little slip-up means the entire mission is bust. (Unless you're playing on easy, and then it's okay to fudge a little.) Swat 4 is an anti-shooter. If you play correctly and complete a mission perfectly, none of your team will have fired a single shot. Your goal is to safely restrain everyone in the area without hurting them (permanently anyway; pepper spray, tazers, or rubber bullets are allowed) and confiscate all weapons. The enemies (and sometimes innocents) rarely want to go quietly, so you'll usually need to resort to one of the above methods of subjugation, or if that fails, shoot to kill. Oh, and there's yelling. Alot of yelling. This is probably the only game made where your first course of action when confronting enemy is to always shout at them at the top of your lungs.
Like Freedom Force, this game starts off fairly simple and easy, but by about halfway through it becomes extremely difficult. Again, I was too stubborn to set the difficulty down to easy, but eventually succumbed to frustration-boredom and put the game down, never to return. I believe I completed about 75% of the game, not including the expansion. The map design is very realistic, portraying a wide variety of indoor locations in extreme detail. There's also definitely a touch of Irrational's twisted nature present, with two missions taking place in some genuinely creepy locations. (Like the lair of a sociopath, and the headquarters of a suicide cult.) If you like serious, realistic games, stealth and non-violent gameplay, to micromanage like crazy, and supreme challenges, I do highly recommend it.