Prototype

An easy way to get experience points is to get a helicopter, preferably without alarm. Go to any Infected area, and search for water towers containing Hunters. These are easily found by going to the area where the crows are circling. This indicates where an Infected water tower is located. Lock on to it, and blow it up with a rocket. It should only take one rocket with a direct hit. You will get 8,000 experience points per water tower. With 200 rockets in an attack helicopter, you can get 1,600,000 total experience points. Then using the machine gun, you can destroy forty more water towers. You can then use the remaining homing missiles to blow up a hive for more points. Get another helicopter, and repeat the process. The water towers will respawn after a short period of time.

Play the mission where you have to steal a helicopter to find the right Hunter. You are told to go fly over the Infected area and scan the Infected water towers for a suitable enemy type. Instead of doing that, fly to the Infected area, and start shooting the Infected water towers that are around all Infected areas. You get approximately 8,000 experience points for each. Shoot 25 of them to get the "Misconception" achievement for destroying the Infected water towers without them hatching. As long as you properly hijack the helicopter and no one suspects you as an enemy, no one will attack you while you do this. One water tower requires one missile. Make sure to steady it so you do not waste missiles. One flythrough with the helicopter can get you 1,192,000 experience points, assuming you can find one water tower per missile. You can get even more than that if you use your machine gun. After getting about 500,000 experience points, crash the helicopter, and repeat the process again from the checkpoint.

Note: This trick requires the ability to hijack helicopters and have Infected Vision, obtained later in the game. Hijack a helicopter, then activate Infected Vision. Look for the bright orange water towers scattered throughout the city, primarily in the Infected areas. Shoot them with the helicopter's weapons. For each water tower destroyed, you will get 10,000 experience points, which are important this far in the game. Note: Water towers respawn continuously for unlimited experience points.

Use the following trick to gain more experience while running. Carry an army truck or another large object and run through the infected people, or collect the genetic materials that comes out of a hive.

The experience points awarded for each Orb that you pick up is based on how many Orbs you have already collected.

Hint Orbs
1: 5,000 each
10: 7,500 each (and 10,000 bonus)
15: 12,500 each (and 25,000 bonus)
35: 15,000 each (and 50,000 bonus)

Landmark Orbs
1: 2,600 each
10: 5,000 each (and 10,000 bonus)
25: 9,750 each (and 25,000 bonus)
100: 15,000 each (and 50,000 bonus)
125: 17, 250 each (and 60,000 bonus)
150: 20,000 each (and 70,000 bonus)

Hold D-pad Down or D-pad Up when using the armor power or attack powers to see an extended change in disguise. Each power except for the Vision Powers has their own mini-cinematic. You can test it with or without the armor on.

Squawking crows usually circle the Infected water towers, making them easier to find.

Successfully complete the game under the Normal difficulty setting.

To do this trick you will need the ability to Jump Kick so that you can fly towards the first helicopter of The Strike team. You can also use the Whipfist's Grab upgrade to latch onto an enemy helicopter. Double Jump can also be useful. To start, jump up and Jump Kick or use the Whipfist Grab to latch onto the first helicopter. Do the button event to kill the pilots. Fly up as high as possible and look for the next target. Make sure to use the Lock On ability. Jump out of the current helicopter and Jump Kick towards the next helicopter. You can keep doing this as long as there are helicopters. If you fall, quickly use the Whipfist Grab. Note: This can be very challenging but if done successfully you can attack numerous helicopters without ever touching the ground.

Successfully complete Story mode. You can now replay Story mode with all powers and upgrades previously unlocked. Note: New Game+ is only unlocked for the difficulty setting that you have completed (and any lower difficulty settings).

Earn a "Gold" rank in all events. Note: This may also unlock some Radical events.

If you want to use or find a Thermobaric tank after the mission where one appears, go to the event "Rolling Thunder". Hop in and cancel the event to use the tank. If you cannot find it or do not know if you have unlocked it yet, pause game play, select "Events", then "Kill" and scroll down until you find "Rolling Thunder".