Well since there is no guide I will add one, even though there is not much to this since the achievement is story related and pretty self explanatory. Some people, like myself, want to do a hard run through on their first go and coming to this fight can be a pain as there are no tips to help during the fight.
There are two parts to this Lockdown fight.
You have to fight off hordes of enemies until Lockdown jumps to the center machine and start to activate it. While doing so you will see him stand on the coolants. A door opens under him while he is doing this. At this point you must shoot into the door to destroy the machine. this will be done one after the other so get ready to circle the machine as you destroy it. Then he will jump to the 2nd at which you will do the same and then right after you destroy it he will jump to the 3rd and final door at which do the same one last time.
DODGING IS YOUR FRIEND! This fight will have you enclosed in a ring where Lockdown hangs from the machine in the middle with an invulnerability shield on him and a riot cannon to blast you with. You have to shoot at him still to make him come down to the ground with you. now at this point DODGING IS YOUR BEST FRIEND! Also keep in mind **MELEE ATTACKS ARE HIS ONLY WEAKNESS**when he is on the ground. now that he is on the ground with you, 1 of 2 things can be done here:
Method 1: you can do a dash in, melee, dash out as quick as you can. you can probably get off about 2-3 of these combos. Then at which point he will run to a position on the floor and do that lame Slow-Mo stomp. This is where he is most DANGEROUS and dodging is no longer your friend. Do not fear though as this is where your shield power is your ULTIMATE FRIEND as you can let him beat up your shield during this phase and get it powered up enough to send the energy back at him BUT only once you regain normal speed. Then if possible you can do the dash in melee dash out tactic one more time then he jumps back on the wall. Also keep in mind, he only does the Slow-Mo stomp every time he comes down. He does the the one stomp but right after he does it he will eventually jump back up and the same process will rinse and repeat till he is dead.
Method 2: the more safe and secure route. almost the same tactic but tweaking when to do the dash in, melee, dash out combo. When he jumps off the wall instead you will immediately pull up your shield and wait for him to do his Slow-Mo stomp get all the power you need and once you regain normal speed send the power back at him and then if you can or want to, do the dash in, melee, dash out combo. then rinse and repeat that till he is dead. this method might take a bit longer to win the fight if you exclude the dash in method but as long as you dodge all his wall attacks and shield yourself against all his ground attacks eventually he will die.
Let me know what you guys think. did it help give thumbs up. if any negative let me know why and i will edit. video coming asap OR if some one want to add one using this tactic be my guest.