Jak II takes the original design formula from Jak and Daxter, adds a few new mechanics, and then makes everything bigger - more missions, more abilities, more variety. Unlike many platformers, however, the gameplay variety does not get in the way of what is a very strong, enjoyable main quest.
The first thing that you'll notice about Jak II is that the game has a much darker tone than the original. Just to give you an idea as to how different Jak II really is from its predecessor, the game starts with Jak being subjected to two long years of hideous experiments. It's only after Daxter (finally) breaks him free that your adventure begins. To give away much more would be doing the game's plot a disservice, but it should be fairly apparent that Jak II isn't your typical feel-good hop n' bop game with a furry mascot.
On that note, the title also takes many cues from more "mature" games, not the least of which is the Grand Theft Auto series. The entire "hub" overworld is essentially a ripoff from Rockstar's opus, right down to the ability to jack hover cars and speed around the city, guided by the circular radar in the corner of the screen. Despite the obvious "borrowing", this mechanic actually works extremely well, and helps to make the beautifully rendered environments seem even more "real". While games like Ratchet and Clank may have lots of traffic zooming in the backdrop of levels, there is nothing like actually zooming through traffic and hordes of pedestrians on your way to the next mission.
Also new to Jak II is the ability to use 4 different weapons. Again, while this new gameplay element is obviously a rip from Ratchet and Clank, it is implimented much better here than it was in that game. Instead of having dozens of weapons, many of which have little practical use, Jak II gradually lets you collect a small but very useful arsenal. Thus, each weapon has a very clearly defined purpose. A surefire favorite will no doubt be the "Scatter Gun," Jak II's implimentation of the prerequisite shotgun which any decent shooter must have. Taking out 10 to 15 enemies with rapidly repeating shots is very cool, and adds the thrill back to a genre where the emphasis as of late has been on exploration, not action.
That's not to say you won't be doing any exploring. Quite the opposite. The hub city not withstanding, Jak II's environments are huge in scope, but also filled with imaginitive and challenging old school platforming. Although the game is 3D, many of the levels have a 2D feel to their action, which means that the action rarely bogs down. There are also some minigames to be found, all of which manage to avoid the mediocrity that usually accompanies such attempts at gameplay variation.
Aside from the superb gameplay, Jak II has some of the best presentation values of any game on any console, period. Its visuals are sharp and defined, and the hustle and bustle of the city streets will no doubt be the visual feat for any competing platform game to outdo. Also, since Jak can now talk, and the gloves that an "E" rating requires are off, Jak II is a much more deeply written game, with far more wit than any platformer to date. The exchanges between Jak, Daxter, and the supporting cast are nothing short of comedic gold at times, and will make even the most jaded gamer crack a smile.
The main quest is a long one, and there are side quests to keep you busy after that. Despite its long length, Jak II doesn't artificially increase its play time by adding endless "collect x number of doodads" type quests. This stands as one of the game's biggest strengths - you actually feel as though you are shooting and jumping for a reason, as opposed to just for the sake of collecting coins or something similar.
There's simply no way around it: Jak II is the platform game they give you to play in heaven.. Even if you're completely burnt out on games of this type, Jak II is that rare game which will rekindle your love for the genre, and remind you just why you started collecting coins, rings, apples and shines in the first place.
-George