Immediately switch to Armor and Blade after the cinematic ends. Having Infected Vision on helps. Keep your distance from the Boss until he starts to jump. After he lands, attack him with an Air Blade Slash so he becomes stunned after a few good hits. Grab him and repeatedly punch. If you are taken down to critical level, use a Devastator move to stun him.
After acquiring the ability to hijack a tank, drive one into a red zone. You will find a lot of fleeing civilians (normal and infected ). Drive on the sidewalk to run them down. You can also unlock "Speed Bumps" after 500 people are run over in a single tank.
The Whip Fist, Shield, and optional Thermal Vision are required. At the start, when you need to collect samples, just run around and collect them. When the Boss comes in, just Whip Fist him. Note: Do not Whip Fist him while he has the electrified Billy club (police stick) or else he will shock you and take away health. When he is shooting you, before he fires he will shine a laser light. Just Whip Fist him and he will take some damage. When he goes up to the roof and the Infected appear, he will come back down in a moment. Do the same thing, only you will be attacked by Infected. This is when Shield is useful. When his friends come down to shoot you, just repeat what you were doing before.
After unlocking the New Game + option for Easy Mode or Normal Mode, you can start a new game plus on a difficulty setting for which it has not been unlocked. To do this, under New Game, select Easy + or Normal +. Instead of saving as prompted however, press CIRCLE to back out of your selection, then select a difficulty for which the New Game + has not been unlocked. Save the data when prompted to start the game. You will start the game with New Game + status, without having unlocked it for the corresponding difficulty setting.
Purchase all upgrades that allow you to do +3 Devastator attacks, upon max health. Get all the upgrades you can via "Consume". Notice that under her life bar are other bars. These are some what the Boss' stabilizers, making her vulnerable only after you have severed them. At the beginning of the battle she will do a scream attack. Be careful. Scale up a building or whatever else you have to do. It is very easy to avoid. You will also have Hunters and Infected chasing you. Use the full body armor and claws/blade. Max out your health by running around and consuming. It is easy and the only issues you might have are Hunters, though with the upgrades one hunter can nearly boost your life to max, allowing for maximum Devastator attacks. This is one of thefirst Devastator attacks you will learn. Scale a building, boost over to her, fall, and initiate the attack. You will see quickly that the Boss' stabilizers are being damaged. Note: Every round the stabilizers' life will increase, meaning that you have to follow the tactics in the same way (and it will just take slightly longer). Strike her with the Devastator. You should have a chance for more, unless she does multiple attacks (green orbs that track you, spitting concrete and screaming). The armor reduces the amount of damage inflicted, allowing you enough time in between attacks to initiate the Devastator again. Once the stabilizers are done, she will fall and you can attack normally. She will then retreat (leaving you plenty of red life orbs to consume) before shooting out of the ground again, with more stabilizer life and "backup". Ignore the backup. This tactic works great, but if you get low on health, run away from her view and keep consuming. After she falls a total of three times you will have defeated her.
The Hammer Fist Power and Hammer Fist Throw are required for this glitch. Find a building with a small wall around the sides or no wall and run to the edge as if you are going to do the hammer throw. When very near the edge, hold TRIANGLE to do the hammer throw. You should slide off the edge and float until your character throws his fist.
After obtaining the Armor Defense power, you will be able to use this trick. It can be used to catch up and attack enemies with force. When you get near an enemy that you can glide over him, revert to normal Alex then initiate a glide. While gliding, activate your Armor Defense power. This allows you to maintain your glide as long as you do not release it or dash. This will allow you to glide over stationary enemies and attack with more force. This is especially useful when fighting Elizabeth Greene (the Times Square Boss).
Remain anonymous and destroy the detectors by hijacking a chopper and letting your disguise meter cool down. Stay at a distance and make sure that the disguise meter is low. Target the detectors and fire the turrets. This will allow you get to the base without detection.
Note: You can probably do this trick with any helicopter. 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, however, fly to the Infected area and start shooting the Infected water towers that are around all infected the areas. You get about 8,000 experience points for each. Shoot 25 of them and you will get the trophy for killing 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 this is happening. One water tower requires one missile. Make sure to steady it so you do not waste missiles. One flythrough with this helicopter can net you 1,192,000 experience points, assuming you can find one water tower per missile. You can earn 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 only works after acquiring the ability to hijack helicopters and have Infected Vision, received later in the game. Hijack a helicopter and activate Infected Vision. Look for the bright orange water towers scattered throughout the level, primarily in the Infected areas. Shoot them with the helicopter's weapons. For each water tower you destroy, you will receive 10,000 experience points, which are vital this far in the game. Note: Water towers respawn repeatedly for unlimited experience points.
To gain more experience while running, carry an army truck or another large object and run through the infected people. You can also collect the genetic materials that comes out of a hive.
Go to the "Close Combat" war event, south of the park, to find a fight going on between hunters and GENTEK Supersoldiers. Do not enter the war event. The Supersoldiers outside the event are significantly different as they do not cause military alerts when you approach them, but they are still hostile. Hold R1 behind them and you can initiate a stealth consume. Note: You cannot become them.
An easy way to gain EP is on mission 22/31. After you steal the Black Ops helicopter, do not destroy the Hive when prompted. You can use the helicopter for as long as you want with its unlimited ammo. Switch to Infected Vision and blow up infected water towers to easily gain EP.
You will need a helicopter and make sure your health is at max. Also, make sure you have the Whip upgrade. Take your time on this one since the longer you spread the mission out, the easier it will be. If your health gets low, bail from the chopper and replenish it. Once on the roof when you start at the facility, turn to the right to see two guards on top of a building across the street. They are shooting rockets down at the crowd. Use your whip and kill both of them. Acquire a helicopter. If there are no helicopters nearby, make enough commotion for a strike team to be called in. Once the chopper is within reach, use your whip and take it over. Every time you take over a heli, you will have about a 30 second grace period before the other choppers start firing at you; use it. Select the heat seekers and blow the other helicopters away, then wait for your threat to go down before you go into the Facility airspace. Once your threat is down, fly over to the Bloodtox Facility. The first things you need to take out are the guard towers. There are about eight to ten of them on all sides and corners. They also have heat seeking missiles. Once the towers are down, the facility is completely open. Beware of strike teams, etc. Save your heat seekers for them and get an aim on them before they do whenever they appear. When all the towers are down, the primary objective is to shoot those small boxes near each of the tanks. They have red blinking lights on them, and there are eight of them. Note: There are other threats in this mission. One of them is the tank that will constantly shoot at you, but not with heat seekers. However, some of the missiles people fire from the ground are annoying. Listen to your helicopter warnings and keep an eye out for other choppers that are getting close to you. The more you take out first, the better.
The ability to Jump Kick is necessary 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. First, jump up and Jump Kick or use the Whipfist Grab to latch onto the first helicopter. Do the button event to kill the pilots, then 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, immediately use the Whipfist Grab. Note: This can be very challenging but if done successfully you can attack numerous helicopters without ever touching the ground.
Hold the D-pad while using the armor power, vision power, shield power, or attack powers to see an extended change in disguise. Each power has their own mini-cinematic, which can be tested with or without the armor on.
Play the mission where you lead the Leader Hunter to Ragland and complete your objectives without being noticed. You will be instructed to lure the Hunter. Look at the map to see that it is mainly infected zones with two blue military zones at the far east and west. Notice the unclaimed area directly up the middle. Stay in this area to avoid alerting the military.
Unlock the "Rolling Thunder" Kill Event that occurs between the East Village and the Lower East Side to find a Thermobaric Tank next to that event. Get into it to activate the event, then immeidately exit before the event actually starts. If done correctly, you will have a free tank. The tank will disappear if you leave the tank or use it to destroy a Hive or Base. However, it can be obtained again where it was found.
After recovering your powers (when Ragland helps you), it will be easy to find infected water towers. Lock on to one and go to the corresponding building. Get on the roof and use the flying kick attack to do significant damage. Then, immediately follow up with a combo to destroy it. Note: The "claws" powers will make this easier.
During the "A New Order", mission , get to the destination point. Instead of starting the mission, wall run up the building directly next to the destination point. There will be a smaller red building (similar to a hideout) on top of it. Punching or kicking that specific red building will be like punching a window or any other glass object.