To the No. 5 Reactor[1] is the third chapter in Final Fantasy VII, part of the first act, "Banner of Revolution". After meeting back at the hideout, Cloud Strife joins up with Barret Wallace and Avalanche to destroy another reactor, this time with the help of Tifa Lockhart.
Walkthrough[]
Leaving Sector 7[]
Upon waking up the next morning after the previous chapter, Cloud wakes up in the underground hideout. Use the elevator on the pinball machine up to the top floor. It is possible to improve Cloud's date mechanics score with Tifa or Barret here, by talking to her and answering "Next to you, who wouldn't?" to increase Cloud's score with Tifa by +5, or "Barret's snoring woke me up" to increase his score with Barret by +5. Either way, to progress, talk to Barret, who will explain that the next target is the reactor in Sector 5 and then ask for help on how to use Materia. Select "Ok, I'll explain it" to be given a tutorial on how to equip Materia, or skip with "You wouldn't understand". Either way, after this, it is possible to use the menu to equip characters with Materia, and Tifa joins the party.
The next destination is the train station again, which requires backtracking to the same train station by traveling east. There is more that can be done in the Sector 7 Slums first. In the southeast building, a weapon store is located on the first floor, and the Beginner's Hall is found on the second. The Beginner's Hall contains tutorials for the game's mechanics, as well as an All Materia which can be paired with Magic Materia to damage all enemies or heal all allies, and an Ether from a treasure chest. Though no new weapons can be purchased at the store, Iron Bangles can be purchased for the party, improving defense and providing an additional Materia slot. The building in the southwest also contains a Materia store, though none of the Materia other than Fire (which is acquired later) are new or are necessary to equip.
After stocking up on equipment, the player should then head to the train to continue.
Train[]
After entering the train, it will travel to Sector 5. However, an ID scan forces Cloud, Barret, and Tifa to run down through the cars to avoid the scan on a timer for each. At most cars, there is the potential to gain or regain an item:
- On the first car, there is a fifteen seconds timer. Running to the back to speak to a non-player character in the back-right of the room will reward the player with a Phoenix Down, before running down and reaching the next car.
- On the second car, there is also a fifteen seconds timer. The non-player character at the front-left will provide a Hi-Potion when answering him with a "Yeah..." when spoken to.
- On the third car, thirty seconds are given instead of fifteen, when a thief robs 100 gil from the player; following the thief up and answering with "That's right" will grant them the gil back. If the player does not have 100 gil, the thief will not do anything.
- The fourth car is on a seventeen seconds timer, and has no items.
- The fifth car has no timer. A cutscene will trigger here, and the group can leave.
If the countdown ends on any of the cars, the party will jump off at Sector 4 early. The car the party jumps off at corresponds to the tunnel arrived at. Lower car numbers means the player jumps off further south in the tunnel, which is further from the storyline goal.
Winding Tunnel[]
After getting off the train from Sector 7 to the Sector 5 Reactor, the party lands in the winding tunnel, which comprises six tunnels. Timing out in Car #1 has the player jump off at Tunnel 2, in Car #2 at Tunnel 3, in Car #3 at Tunnel 4, in Car #4 at Tunnel 5, and making it to the end leaves the player at Tunnel 6, right at the end. Walking back past Tunnel 1 will cause the player to enter the danger area, where Special Combatants are fought endlessly. These enemies deal more damage and have more HP than most random encounters, and as they are completely optional to fight, they are best off avoided.
Throughout the winding tunnel, Grashtrikes, enemies which deal little damage and can be defeated in 1-2 hits, can be fought to obtain Spider Webs; Rocket Launchers can also be fought here, and though their main attack can deal decent damage to the character with the lowest HP, their attacks are slow, and they can be focused down to destroy them before firing.
Traveling forward through the winding tunnels will lead to the security sensors. It is impossible to progress through the tunnel past these, so instead, the player must interact with a duct on the left and select "Go down" to proceed to crawl through the first duct, leading to the Lower Sector 4 Plate.
Sector 4 Plate[]
In the Sector 4 Plate, Chuse Tanks and Blugus may be fought. Chuse Tanks have low HP but can deal considerable damage, meaning they should be prioritzed first; conversely, Blugus have high HP but deal minimal damage.
Continue through the first duct, at the end of which is the ladder room, which leads down into the big room. Both the ladder in the middle or the ladder on the left-hand side will eventually lead to the small room, where the player will find Jessie. A ladder on the left of the small room leads down to the exit.
After reaching the exit, the player can use the save point, before taking the duct into the Sector 5 Reactor.
No. 5 Reactor[]
The No. 5 Reactor is entered through the Lower Sector 4 Plate - Exit, and the party arrives in the room with the main staircase. From here, the player must descend down through the piping at the bottom floor of the staircase to the core, fighting random encounters with the Smogger, Special Combatant, and Proto Machineguns. Smoggers have higher HP but deal minimal damage; Special Combatants have less comparatively HP and deal more damage, meaning they should be prioritized first; Proto Machineguns are slow but have higher HP. To help deal with them, the Lightning Materia can be paired with All, to deal damage to all enemies with a single spell.
When reaching the lower piping, Blood Tastes can also be fought as well. These enemies deal fair damage, but can be defeated in a few physical hits. Upon reaching the core, a cutscene will initiate and AVALANCHE plants the bomb. Unlike the previous reactor, there is no timer and no immediate boss battle after doing this.
Once the bomb is planted, the player must then ascend back up to the main staircase by retracing their steps, and climb the central structure to a door at the very top of the room, where the elevator is located. This will take them up to the entrance of the Reactor where they will leave. A minigame is required to unlock the door, and upon leaving, the player must fight Air Buster.
To open the blocked off door at the reactor's entrance, the door can only be opened through a terminal in the room to the left of it. Cloud, Tifa and Barret must all press the button simultaneously in order to open it. The player controls Cloud, and must press the button (
on PlayStation, [OK] on PC, 
on PlayStation 4, 
on Nintendo Switch) closely in time with the others. The other two will press the button approximately two seconds after Tifa announces it, which the player must time.
After opening the door, before proceeding, it is advisable to equip the party with the Lightning and Restore Materia, preferably on different characters, so once character can cast Bolt to exploit Air Buster's weakness to Lightning while another can heal in a bind. During the boss battle with Air Buster, the player can take advantage of the positioning by attacking with whichever character it is not facing to deal double damage.
After Air Buster is destroyed, a short scene commences. When Cloud is barely hanging following an explosion, the choice can affect date mechanics; selecting "(Be strong)" improves Cloud's score with Barret by +2, while "(I don't know if I can hold on)" reduces the score with Barret by -3, and increases it with Tifa by +1. The quest that follows is "The Woman at the Church", commencing in the Sector 5 slums church.