Jak & Daxter was greatly inspired by Mario 64 and past Naughty Dog games; its big achievement, and probably the only great novelty introduced in the game, was the continuous game world, which replaced the discreet level structure of Mario 64. Jak II, while remaining a platformer using game mechanics similar to its predecessor, takes inspiration also from the latest two Grand Theft Auto games and from Ratchet & Clank (developed by Insomniac Games, a team that has always been very close to Naughty Dog).

From Grand Theft Auto, the game borrows the urban landscape, Haven City, which basically works as a central hub that serves as an access to the many missions. Haven City is really more similar to Vice City than you would expect; it has civilians walking in the streets, policemen (Praxis's red guards), and many story characters that will ask you to complete tasks for them. A map on the right lower corner of the screen works exactly as the one featured in Grand Theft Auto games; icons show you the direction, relative to your current position, of story characters and places that you must visit to proceed in the adventure. Many of the missions are entirely optional, but can reward you with prizes useful for the main adventure. Resemblances with Vice City don't stop here. You can hit civilians, and even kill them (this is not justified in any way by the storyline, though), and you can steal hover cars (called zoomers) moving through the streets of the city by simply pressing - you guessed it - the triangle button; vehicles, which come in about 10 different models, are not easy to handle and need a bit - or a lot, depending on the player - of practice, also because Haven City is entirely made of narrow passages and streets that make driving through the continuous traffic without hitting one of the numerous zoomers almost impossible. It can be fun to drive the zoomers and switch between the two different hover heights pressing the R2 button, but many players can find the driving experience in Jak II excessively unforgiving and frustrating, which is something you wouldn't expect from the developers of the original Jak & Daxter. Red guards will also start chasing you, until you are dead or you manage to escape, whenever they spot you making a wrong move - which can be stealing vehicles, hitting other zoomers, or killing civilians. Escaping isn't always easy, because of the narrow streets of the city and because a few shots are sufficient to kill Jak. Honestly, the whole Grand Theft Auto thing feels often gratuitous in Jak II, and it happens often to miss the free, rarely frustrating, world of the past game; after the initial surprise, it's easy to get bored of the navigational sections through the streets of Haven City, which, after all, offers little interactivity to the player.

Anyhow, Haven City remains a hub that doesn't eliminate the fact that Jak II is still, substantially, a platform, a mix of the past game and Insomniac's Ratchet & Clank. From the opening sequence, in which Jak must escape from the prison jumping from platform to platform, to good part of the other missions, Jak II offers plenty of double, high, and long jumps, moving platforms, unstable platforms, platforms made of decaying materials, Crash-Bandicootesque spin attacks, jump attacks, and so on. The main difference from Jak & Daxter is that Jak II is no longer entirely based on collecting items, even if a lot of optional quests still asks the player to find orbs, gems, and similar stuff to enhance your character - and, in the end, you will collect this stuff, trust me.

This doesn't mean that Jak II isn't an enjoyable game, or that the missions aren't varied. On the contrary, as you would expect from those good guys at Naughty Dog, controls are excellent and fluid, missions offer always-different challenges, and lots of classic mini-games make the experience a bit more varied. Coming from Ratchet & Clank is Jak's morph gun, which, through its four different upgrades, gives Jak the chance of having a shotgun, a machine gun, a rifle for long-range attacks, and the deadly Peacemaker. As Ratchet & Clank already proved, weapons fit perfectly in the platformer genre, and Naughty Dog just confirms this with the brilliant implementation of weapons in Jak II over a classic platformer structure. Jak can also turn into Dark Jak, the hulk-like thing I mentioned earlier, thus becoming much more powerful in melee combat. Anyhow, since it requires a good amount of Dark Eco (see, collecting is still here) to turn into this form for a mere few seconds, this feels more like an extra than a well implemented gameplay feature. Other extras include the Titan Suit, a sort of mech suit (fans of Alien will love it) used in the last levels of the game, and the more common Jet-Board, a hovering skateboard well integrated in the platforming missions that you get after a few hours into the game. Daxter has also a couple of funny, solitary missions.

Overall, Jak II offers a fun, varied, truly vast experience with some questionable design issues that make the game less fresh, less balanced, if you want, than its predecessor.