Resident Evil 4 remake has several bonus weapons. We’ve already covered how to grab the Handcannon and how to unlock the Infinite Rocket Launcher, but if you’re looking for a melee weapon to compliment them, you’re probably going to want to get your hands on the Primal Knife.
The Primal Knife is one of the most powerful melee weapons in Resident Evil 4 remake, and the only knife in the game that can be made unbreakable, so there are definitely plenty of reasons to hunt it down. Here’s how to unlock it.
How to Unlock the Primal Knife in RE4 Remake
To unlock the Primal Knife in RE4 remake, you’ll have to go collectible hunting. That means destroying 16 Clockwork Castellans, one per each of the game’s chapters. Popping all 16 Clockwork Castellans will complete the Revolution Wind-Up challenge and unlock the Primal Knife.
The only problem is that they’re hard to find. Not to worry, though. We know where all of them are.
Where to Find All Clockwork Castellans in Resident Evil 4 remake
Clockwork Castellan 1: Chapter 1 — Lakeside Settlement
Your first Clockwork Castellan is on the roof of the cabin in Lakeside Settlement, which is the first place you’ll meet Luis. You can snipe it through a hole in the cabin’s roof.
Clockwork Castellan 2: Chapter 2 — Abandoned Factory
You’ll find the second Clockwork Castellan in a cabin north of the Abandoned Factory, just to the right of the entrance. This one’s easy to remember, because you’ll meet the Merchant for the first time here.
Clockwork Castellan 3: Chapter 3 — Quarry
You’ll find this one in the Merchant’s house in the Quarry. Take the ladder down and follow the ticking noise. The Clockwork Castellan is hidden behind a group of boxes in the right corner of the area.
Clockwork Castellan 4: Chapter 4 — Lakeside Settlement, Near the Forest Altar
After you take out the Lake Monster, take the boat back to the Lakeside Settlement. You’ll find your fourth Castellan behind the fences at the Forest Altar. If you’re having trouble, look for the body of the poor girl who was sacrificed. You’ll find it near her.
Clockwork Castellan 5: Chapter 5 — Village Square, in the Village Chief’s Manor
When you return to the Village with Ashley in Chapter 5, head to the Village Chief’s manor. Pull the level behind the painting on the second floor to release a secret ladder. Take the ladder up to the attic to find the Castellan.
Clockwork Castellan 6: Chapter 6 — Bridge North of the Villa
You’ll come across a Bridge in Chapter 6 that leads to an area weirdly called Checkpoint. You’ll find your sixth Castellan sitting in front of the bonfire to the right of the bridge.
Clockwork Castellan 7: Chapter 7 — Dungeons
Be sure you grab this one before you leave the dungeons after you kill the Garrador. Once the Garrador is done and dusted, climb the ladder behind the locked gate. You’ll find the seventh Clockwork Castellan sitting on top of the shelves there.
Clockwork Castellan 8: Chapter 8 — Castle Battlements
You’ll know you’re in the right place because an armored version of El Gigante will be throwing big ol’ rocks at you. Ignore him, and head to the tower on the left side of the area. The Castellan will be on the right side, just in front of the boxes.
Clockwork Castellan 9: Chapter 9 — Courtyard Maze
This Clockwork Castellan is in the upper left side of the Courtyard Maze. Here’s an easy way to get there: after you take the steps down, skip the first exit on your left and take the second one. From there, turn left at every corner. You’ll eventually find the Castellan behind a table.
Clockwork Castellan 10: Chapter 10 — Depths
You’ll find this one in the tunnel that connects the depths to the Merchant’s location. Look for the area that’s gated off from the Merchant’s area, and you’ll find the Castellan hanging from the ceiling.
Clockwork Castellan 11: Chapter 11: Stopover
This Castellan is found in stopover, which is where you and Luis stop after riding the minecart for the first time. Look for the broken-down structure at the top of the area, and you’ll find the Castellan hiding on the roof.
Clockwork Castellan 12: Chapter 12 — Clock Tower
You’ll find this one after you ride the cable car north of the Ballroom to reach the Clock Tower. The Castellan is sitting on top of some tarp-covered boxes in the bottom left corner.
Clockwork Castellan 13: Chapter 13 — Wharf
There’s an area littered with cars and sipping containers just north of the Wharf. You’ll find the 13th Clockwork Castellan behind the green forklift, sandwiched between it and a brown truck.
Clockwork Castellan 14: Chapter 14 — Amber Storeroom, near the Campsite
At the Campsite, you’ll find a small room across from the gate near the giant amber. Look for this Clockwork Castellan sitting atop the lockers in that room.
Clockwork Castellan 15: Chapter 15 — Specimen Storage
This is the area with all the hanging body bags. You’ll find this one in the room just right of the area labeled Specimen Storage on your map, up in the rafters. Use your flashlight to help you spot it.
Clockwork Castellan 16: Chapter 16 — Underground Passage
You’ll snag your final Clockwork Castellan just before you and Ashley hop on the jetski in the game’s last chapter. This one is behind the green forklift in the Underground Passage.
Destroying all 16 Clockwork Castellans unlocks the Primal Knife and the Revolution Wind-up achievement or trophy, depending on your platform of choice. Congratulations on unlocking your newest bonus weapon. It’ll help you immensely during the Krauser fight. For more help with Resident Evil 4 Remake, check out our RE4 guides hub.