Escape from the Reactor, Rendezvous with Barret (バレットと合流, Baretto to Gōryū?), and Sprint to Safety (逃走経路へ急げ, Tōsō Keiro e Isoge?, lit. Hurry to the Escape Route) are the final missions of Chapter 1, "The Destruction of Mako Reactor 1", in Final Fantasy VII Remake, taking place in Mako Reactor 1. After setting the charge in the Mako Reactor 1 and destroying Scorpion Sentinel, Cloud Strife and Barret Wallace flee the reactor before it is destroyed.
Walkthrough[]
With Scorpion Sentinel destroyed, Barret leaves the party. Run to follow Barret and climb the ladder, then head left up the ramp. Two Monodrives are fought along the way, both of which can be destroyed quickly. Follow Barret up the ladder, after which a short scene commences and Cloud hangs from a railing. Head left across the railing to help Jessie. This commences "Rendezvous with Barret" briefly.
Potions chest.
Follow Jessie down a ladder, across more scaffolding, and she will reach another ladder. A chest containing two potions can be opened adjacent to the ladder before climbing it. After climbing it and another ladder, Cloud reunites with Barret, concluding "Rendezvous with Barret" and continuing "Escape from the Reactor".
Barret rejoins the party, as security officers and Monodrives are fought. Much like before, these enemies can be destroyed quickly with a single ATB command or Overcharge, and a few attacks. Following this, head through the hallway to the sweeper room, where an active sweeper can be fought. As before, Barret can use 
Thunder while Cloud uses Focused Thrust to stagger it, at which point the two can lay into it with Braver and Thunder to destroy it. Though it is also possible to simply run from the fight, doing so will miss out on rewards of gil and EXP, and the enemy can still destroy it within the time frame.
Head up the stairs, where four more Monodrives appear. Past them are shock troopers, which are more challenging enemies that can evade attacks. After it evades the first few attacks, switch to another character and use either an ATB command or Barret's Overcharge to deal heavy damage before it evades attacks again, at which point the process can be repeated. Head up the stairs where two Sentry Rays and two more Shock Troopers are fought; the Sentry Rays are easily dispatched with Barret, while against the Shock Troopers, the same strategy applies as before, but Cloud and Barret must frequently roll to dodge their attacks to prevent them interrupting. After they are all passed, run to the elevator and press the button, at which point a cutscene commences.
At the end of the scene, "Sprint to Safety" commences. For this, simply run out of the reactor, following Jessie, and a cutscene will commence shortly after escaping the reactor. Following this, the chapter is concluded, continuing in "Fateful Encounters" with the quest "Use the Escape Route".
Hard mode tips[]
The timer is restricted to twenty minutes, but the quest is otherwise unchanged. Cloud can make use of Triple Slash effectively to clear waves, and with 
First Strike Materia, can open battles with it. Against the shock troopers, Barret's Maximum Fury is effective.