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.
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.
-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 achievement 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.
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.
When just short of an upgrade at a checkpoint (for example, at 90,000 experience points for the 100,000 experience point upgrade), earn the experience points needed. Purchase the desired upgrade with the experience points, then kill yourself to return to a checkpoint. You will have both the upgrade and the 90,000 experience points previously earned at that checkpoint.
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.
Collect the following amounts of orbs to gain the corresponding amounts of experience:
Landmark orbs 1 orb - 2,600 XP each 10 orbs - 5,000 XP each (+10,000 bonus) 25 orbs - 9,750 XP each (+25,000 bonus) 100 orbs - 15,000 XP each (+50,000 bonus) 125 orbs - 17, 250 XP each (+60,000 bonus) 150 orbs - 20,000 XP each (+70,000 bonus)
Hint orbs 1 orb - 5,000 XP each 10 orbs - 7,500 XP each (+10,000 bonus) 15 orbs - 12,500 XP each (+25,000 bonus) 35 orbs - 15,000 XP each (+50,000 bonus)
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.
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).
Contrary to popular belief this Boss battle is easy. Long before the battle, purchase all upgrades that allow you to do +3 Devastator attacks, upon max health. It is also a good idea to get all the upgrades you can via "Consume". The Boss is massive. 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 your first 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 nicely, 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.
-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.
-At the start of the battle, use your armor power and hook power. Then, begin using one of the following tactics:
Tactic 1 Keep him locked on. Hold [Jump] for a while to get reasonable air. As soon as you jump, hold [Attack] button and allow it to fully charge. Then, immediately repeat. This should take four stuns to kill him. Do not bother disguising as the military will barely bother with you.
The first stun The Supreme Hunter will be stunned very quickly from this. As soon as you are locked onto him and press [Grab], you should hook onto him and immediately be able to start punching him. Instead of button bashing, press [Attack] at an easier rate than you normally would. It will register more and you will attack faster. After the first stun, which comes very quickly in the battle, he will finally get the chance to use most of his attacks out on you.
His attacks Normal Attack: His normal attack is usually swiping at you with his fists and will fling you into the air. These are very easy to evade. If you are having trouble, try jumping then air dashing away or over him.
Throwing: Around the battle area are many explosive props which he will pick up and throw at you if you are far away. This is rare however, and he will usually miss. Spike Attack: When he uses his attack, it is a very good idea to jump and double air dash away from him as much as possible. As soon as the spikes have shown themselves, it is useful to run at him quickly and get a few good charged slashes into him with your blade. You should not need to do this until after stun two.
Devastator: This is very easy to dodge. He will stand still and start to spasm a bit before he unleashes his Devastator. Do not stand close to him during this time, as he can unleash an instant kill on you even when wearing armor. Instead, lock onto him and air dash around him in a circular radius until the main large tentacles have tried to hit you. Once they have missed (there are about three or four of them), find a spot clear of the large tentacles and change to blade power. Start swiping at him with slightly charged blade attacks. You should be able to get your first hits into him while the tentacles are still moving out and not retracting. You can also get hurt while they are retracting; try not to run into them.
Repeat "Tactic 1" and counter his Devastators when you can. You will eventually stun him for a second time and you should encounter a cinematic during or slightly after the second stun. After the cinematic, you will realize that you have a time limit to kill him. Do not worry about it. Just repeat the first tactic and he will eventually die. You should not need to use "Tactic 2" unless playing on Hard mode or running low on time.
Tactic 2 Wait for the Supreme Hunter to land after a jump and slash him from behind with a few slightly charged blade attacks. As he turns to attack you, jump and air dash over him. You may choose to aerial attack him with a kick or slash him and then jump away. This will lower his health quickly, combined with attacking him during Devastators and spike attacks. This is advised only if you are really running low on time and have just finished stunning and hitting him.
Depending on whether you are still using "Tactic 1" (recommended), you should be able to quickly finish off the hunter within two more stuns. There are four stuns in total. Each stun should take away about 25% of his life under the Medium difficulty setting. If you are using the blade tactic, you will probably encounter him for longer and may get less stuns on him.
Healing You should not have to heal before the cinematic. However, if you do get hurt badly during the second half and there are no people to consume, either stay with "Tactic 1" and jump kick him, or run to the part of the ship with the turrets (the tower object) and jump behind it into the water. As you jump back out, press Forward against the ship and you should hit the ship while coming back up and fall back into the water. Try to press [Grab] onto the side of the ship and heal there if possible. The Supreme Hunter should not be able to hurt you there. Just remember you have a time limit.
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.