Once Human
Image: Starry Studios

Securement Silo Phi walkthrough – Once Human

A scary umbrella.

Securement Silos in Once Human are a fantastic way to quickly rack up those harder-to-find resources like Energy Link and Stardust, both solo and with a team. Securement Silo Phi is the second one you will come across in your Once Human journey, and it contains a few hidden bosses and secrets.

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How to find Securement Silo Phi

This is the second of the Securement Silos you should be looking to hit. I would recommend around level 25 in Once Human before really getting into it. Like most of these, you can go in earlier if you’re playing with some friends. The mini-bosses are a challenge, but nothing too bad.

How to find and clear Securement Silo - Phi in Once Human
Screenshot: PC Invasion

You will find Securement Silo Phi to the East of the Greywater Industrial Zone settlement in the Iron River region of the map. It is a cave on the side of a cliff face, and to begin the area, simply walk right in.

Securement Silo Phi walkthrough

Before you stroll into the Silo, ensure sure you have some decent weapons, healing items, and enough ammo to kill a fair amount of enemies. Make sure to bring Molotovs for one section of the dungeon. Tier 3 weapons and armor should be more than enough for you to do the damage you need in Securement Silo Phi. Of course, with a squad, lower is possible, but this is what I recommend.

As with every one of these levels, I suggest using thrown barrels as much as possible to preserve ammo. Also, snapping with Q will reveal any missed collectibles once you have cleared a room.

  • Make your way down the first corridor towards the room at the end. This room will have numerous zombies and purple enemies among the shelves. Clear this room and collect your loot before moving on to the next area of the walkthrough by heading through the door to the left of the room.
  • Once through the door head immediately left into a corridor with a fan at the end, and left again at the end. This room will have three easy enemies, but more importantly, a purple chest containing a keycard. Make sure to grab this before heading back to the first corridor after the shelves room.
How to find and clear Securement Silo - Phi in Once Human
Image: YouTube
  • Work your way through the area, killing the enemies as you go and making sure to click Q and collect the various chests until you reach an open, red room containing more enemies.
  • When you enter the room, directly to your right, you will hear a gear chest. It is locked behind thorns. Use your Molotov to clear the thorns and get that sweet Once Human Securement Silo loot.
  • Clear the low-level enemies in this section of Securement Silo Phi, and head to the far left of the room to find the first of the Once Human bosses. Enter the elevator and head up to your first fight of the walkthrough.

Rainfall Reaper

Once you reach the top of the elevator, head down the corridor until you pass the doors at the end. You will hear a phone ring. Head back to the reception desk and answer it. You can now head back down the corridor and through the door at the end into a padded room. This will trigger a strange cutscene, after which you can head back through the doors and out of the padded cell.

Securement Silo Phi Once Human
Image: YouTube

This boss is remarkably easy for a Once Human Securement Silo enemy. She is floating just by the tank in the middle of the room. Ignore the other enemies and kill her quickly, it shouldn’t take more than a minute. As soon as she has been killed, a portal will open up.

Head through to collect your boss loot for Securement Silo Phi. The sector is now clear, but if you collected the keycard from earlier, you could face another boss for more Energy Link and Stardust Source.

Head back through the corridor, down the elevator, and back to the red room to continue with the optional Securement Silo Phi Walkthrough boss.

Securement Silo Phi optional boss

Once you have entered the red room, look for the area that has the thorns and the weapons crate. To the left of this, you will see a door sealed with a panel. Using the keycard you picked up earlier, you can access the optional boss for Securement Silo Phi.

This boss room can be overwhelming due to the ADS everywhere. However, if you focus on the objectives it can be cleared very quickly.

  • Seek out the four purple glowing spawn eggs around the room and destroy them as quickly as possible.
  • The boss will spawn in the center of the room once the eggs are destroyed. Throw the explosive barrels dotted around the room at it. This will quickly stagger and drop its health almost to zero.
  • Use your weapon to finish the Securement Silo Phi optional boss off. Clear the remaining ADS and start looting.

There is a lot of loot in this room. You will find it located in the various train carriages and flatbeds. Use your click with the Q button to quickly ping them up on your visuals. Make sure to grab your boss’s loot, too, for a ton of Energy Link and Stardust Source.

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Leo Gillick
Leo is a Freelance Writer for PC Invasion. He has a degree in English Literature and Film Studies and more hours buried into videogames than he cares to admit. He has worked extensively in the Videogame and Travel writing industry but, as they say, get a job doing something you love and you'll never work a day in your life. He uses his writing as a means to support indefinite global travel with the current five year plan seeing him through Latin America.