Overweight override:-  When you build your AC, you will notice that there is a weight limit on the selected legs. To override this, just finish the game so the overall % under system reads 100%. To do this, just complete every mission. Keep in mind that while you can load any leg type with whatever you want after you get 100%, your speed will decrease about 2 1/2 for every hundred pounds that you are overweight.

Sword wave:-  Get Human Plus mode a few times. Then, draw your sword and press X (jump) just before the downslash. If done correctly, you will fire the fabled "wave" that all of the higher ranked ACs use. To fire the "blue wave of mass destruction", simply  do this trick with the Moonlight blade. It can do over 1000 AP worth of damage. 

Taking missions:-  When taking missions, check the sender. If you take too many from one company, others will stop sending you missions. However, after you complete the game you can still play the missions and get the money. Then, all the missions will be  available to replay as many times as desired.

Defeating Phantasma Stinger:-  Buy the arms that are bazookas. Dash on the ground while holding L1 or R1 and fire a continuous volley of shots. You should defeat him in less than a minute.

Glitch: Shoot through city building:-  Equip either one of the grenade launchers, and go to the City Map location in two player split screen mode, arena battle, or linked play. Move right next to a building and face directly at it. Fire a grenade at the other player's AC unit. The projectile will pass through the building without immediately exploding, and you will have the protection of a building from enemy fire. Note: This will not work if you are at an angle -- you must be facing the building directly, with the tip of the gun touching the wall.