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https://psnprofiles.com/?psnId=mrrj46 and
https://psnprofiles.com/VanqishdAfter beating the game, a new set of Shinra VR Simulations will be available in Hojo's Lab (Chapter 17). You can load it up anytime and head to the VR simulation. To get to the Shinra VR challenges, start Chapter 17 and make your way up the elevator to the main level of Hojo's laboratory, you'll fight some Unknown Entities and then your party will move some debris out of the way. After that, you'll encounter Chadley who will tell you he needs your help with his newly reconstructed combat simulator which is also located there on the main level of the laboratory.
Malboro is found in the "Three-Person Team vs. Monsters of Legend" challenge. Even if you load the chapter in Easy or Normal difficulty, you will face the enemies in the challenge in Hard (therefore, items cannot be used).
You will want to make sure each person in your party has revive materia and healing material. It's also recommended that Cloud links Magnify materia and Healing materia together so that when Cloud heals himself, the rest of the party gets healed as well.
You will face enemies in this order:
Boom
This fight shouldn't be troublesome, it gets staggered pretty quickly.
Tonberry
Similar to when you fought Tonberry during Chapter 14 side-quest. The A.I. will almost always dodge Chef's Knife. Avoid standing face to face with it and it shouldn't kill you in one hit, always try to attack it from behind.
Behemoth
Similar to when you fought Type-0 Behemoth during Chapter 14 side-quest. Cripple him by focusing on the lower and middle parts of his body and hit him hard when he's staggered. Do not hit him with magic, as 1) it won't be effective, 2) it will go on "Rampage" status for a short period of time and it will be extremely hard to survive.
Boom + Tonberry
Not much different from the individual fights. However, focus on the Boom and kill it ASAP, since it will grow quickly in size if you ignore him and wipe your party with Self-Destruct.
Malboro
This is possibly the easiest fight in the simulation. His only dangerous attack is Bad Breath. Get hit by it once with the Enemy Skill Materia equipped to gain its Bad Breath ability and dodge it the following times. When it casts it, it will aim at you and follow you for a short period of time, when you're able to move without it following your moves, simply sneak behind him and safely hit him from the back.