Jak II is more than the average platformer. While Mario can only run and jump (and occasionally throw fire), Jak can wield powerful weapons, drive exciting hover vehicles, and pilot a mech! His arsenal is comprised of the following items:
Scatter Gun (handgun):
This is the first gun Jak gets, and it is obtained very early in the game. The Scatter Gun behaves a bit like a shotgun. It shoots a wide shockwave (about 120°) a short distance, and any enemies hit are knocked back, making it easier to deal with them. It's best used when you're either attacking quick-moving enemies or being bombarded by a lot of enemies. It has the second slowest rate of fire in the game, but the wide range makes up for it. The Scatter Gun can hold 50 rounds when it is first obtained, its capacity can be upgraded to 100 rounds later in the game, and ammunition is continuously available in crates.
Blaster Weapon (handgun):
The Blaster Weapon is found shortly after the Scatter Gun, and it is easily the most versatile weapon in the game. It is a long range, laser sighted rifle. It will take down most enemies in two to three shots, and Jak auto-aims this weapon toward enemies. It has a good rate of fire, and its range allows you to snipe groups of enemies before engaging them. The Blaster Weapon can hold 100 rounds when it is first obtained, its capacity can be upgraded to 200 rounds later in the game, and ammunition is continuously available. You'll be using this gun a lot.
Vulcan Fury (handgun):
The Vulcan Fury is found relatively late in the game, but it's worth the wait. This gun is a machine gun with an extremely fast rate of fire, and it is meant for crowd control. Like the Blaster Weapon, it is laser sighted, and Jak auto-aims toward any enemies. It has a shorter range than the Blaster Weapon, but the rate of fire (which increases the longer the trigger (R1) is held) allows you to move in closer and take down a pack of enemies. The Vulcan Fury can hold 100 rounds when it is first obtained, and its capacity can be upgraded to 200 rounds later in the game, but ammunition for this weapon is scarce so it should only be used when no other weapon make sense.
Peace Maker (handgun):
You get to see the Peace Maker in action a long time before you have one of your own. This is Sig's weapon of choice, and it is the most powerful weapon in the game. A single shot can easily take down a group of 10 enemies. Using this gun correctly takes some practice, however, as it requires a charge time to be used to full effect. Its rate of fire is painfully slow, its ammunition capacity is a mere 10 rounds, and extra ammunition is very scarce. The sheer power available is a godsend in boss battles, but it's not meant for constant use.
Gun Pod (turret):
The Gun Pod is accessible only from the Drill Platform. It has a decent rate of fire and is very strong, but it is prone to overheat. If the heat guage goes through the yellow and red levels and maxes out you will be unable to fire until the gun has cooled. Since the Gun Pod is an enclosed turret, its health replaces Jak's while being used (this is a good thing as the Gun Pod has 16 HP compared to Jak's 8). There is no choice about using this weapon; it is required for some missions, and it is unavailable at all other times.
Krimzon Guard Vehicles (vehicle):
The Krimzon Guard have Hovers and Zoomers that are unavailable to the general public, but they can be stolen just like any other vehicle if you don't mind the alert that comes with it. Krimzon Guard Hovers and Zoomers, two-seat and one-seat vehicles respectively, both come with dumb-fire laser cannons. These can come in handy if you know you want to wreak some havoc, but you could always just equip a handgun one one of the regular vehicles without raising an alert.
Hover (2 passengers):
Hovers are the cars of Haven City. They're bigger than Zoomers, can seat two passengers, and can take more damage. If you're going to be running from the Krimzon Guard, take a Hover. The extra durability of the Hover is worth it, and the guards are bad enough marksmen that you still won't get hit very often. Hovers come in two varieties: slow and fast. The slow ones look just like cars without wheels, and the fast ones look like two Zoomers strapped together.
Zoomer (1 passenger):
If Hovers are like cars then Zoomers are like motorcycles. They're small, fast, maneuverable, and easy to destroy. If you're racing or need to get somewhere fast, take a Zoomer; otherwise, take a Hover. The Zoomers are fun to drive, but they're difficult to shoot from, and they're prone to explode from a big crash.
Krimzon Guard Hovers and Zoomers:
The Krimzon Guard Hovers and Zoomers are each a bit bigger than their civilian counterparts. They both come with a vehicle-mounted laser cannon, and they're faster than normal vehicles. Watch out, though. If you steal one, an alert will be raised and all the other Krimzon Guards in the area will be after you.
Hoverboard (1 passenger):
The hoverboard is one of Keira's inventions. It works like a skateboard, and it's a lot faster than moving around on foot in areas when the Hovers and Zoomers can't go. It's extremely manueverable, and some missions require it. The only real downside to the Hoverboard is that you can't fire any weapons from it which makes Jak a sitting duck while using it. There are also some optional hoverboard challenges in the arena where the object is to accrue points by doing tricks.
Titan Suit (mech suit):
The Titan Suit is used to break down walls and manuever in dangerous environments. It is only available for three missions, and it controls just like Jak does except you're slower, you can't double-jump, and you don't have any guns. It does, however, allow Jak to survive underwater for extended periods of time, and it's handy for breaking down walls and columns.