Warhammer 40,000: Boltgun 2 — All Blood Cascade Collectibles Location Guide

Blood Cascade hides five collectibles across its blood-slicked halls: four Secrets and one Purity Seal. Each one sits behind a hidden skull switch that you have to shoot from a specific vantage point, and every pickup lands off the main objective path. Work through them in level order, from the red and purple doors near the start to the collapsing arena at the end, and you will clear the whole set in a single run.

Quick answer: There are 4 Secrets and 1 Purity Seal. Shoot the hidden skull switch tied to each one, then grab the pickup it reveals to advance the Secrets and Seal counters.

All Blood Cascade collectibles and rewards

Collectible	Reward	Where to trigger it
Secret 1/4	+79 Faith	Across the gap by the red [Σ] and purple [Φ] door
Secret 2/4	Grenade Boost	Below the purple key [Φ] balcony
Secret 3/4	Machine Spirit	Drop area past the first yellow door [Ψ]
Purity Seal 1/1	Purity Seal	Outside the second yellow door [Ψ]
Secret 4/4	Infinite Ammo	Large arena past the second yellow door [Ψ]

Secret 1: Skull by the red and purple doors

The first Secret sits near the red [Σ] and purple [Φ] door, and it is easy to walk straight past. You reach it by climbing to an elevated spot and shooting a small skull mounted on the far side of the cavern.

From the area in front of the two doors, head up the ramp opposite them and climb the pipes on the platform to reach the higher vantage point.

Turn around and look across the gap. Line up the small skull fixed to the structure on the other side and shoot it. This opens a lit compartment in the wall.

Jump across into the newly opened opening to grab the pickup. You will see the SECRET DISCOVERED prompt and gain +79 Faith, pushing your counter to Secrets 1/4.

Secret 1/4 Location & Demonstration — Shooting the skull across the cavern from the raised platform opens the wall compartment for Secret 1. Shown at 00:39 in Trophy Tom’s video. Image: Auroch Digital

Secret 2: Grenade Boost below the purple key

Secret 2 triggers the moment you collect the purple key [Φ]. Act quickly, because the skull you need is easy to miss once you turn to leave.

Pick up the purple key, then step out onto the balcony edge in the same hallway.

Look right and across the chasm to spot the skull switch resting on the structure opposite. Shoot it to open a recessed alcove below you.

Descend straight down, then pivot toward the alcove. Pick up the Grenade Boost; You discovered a Grenade Boost! appears, and Secrets advances to 2/4.

Secret 2/4 Location & Demonstration — The Grenade Boost waits in the alcove you drop into after shooting the skull by the purple key. Shown at 01:03 in Trophy Tom’s video. Image: Auroch Digital

Secret 3: Machine Spirit past the first yellow door

Beyond the first yellow door [Ψ] you reach a bridge that overlooks a large drop area. The third Secret is tucked onto a lower ledge, revealed by a skull near the pit.

Cross the bridge over the drop and look down the far hole to find the skull sitting on the spikes and the Secret held behind the bars.

Shoot the skull to open the way through, then drop onto the lower platform.

Grab the Machine Spirit to trigger Machine Spirit: Praise the Omnissiah! and advance the counter to Secrets 3/4.

A Machine Spirit upgrades whichever weapon you are holding when you pick it up, so switch to the weapon you want buffed before you touch it.

Secret 3/4 Location & Demonstration — The Machine Spirit sits on the lower platform you drop to after shooting the skull on the spikes. Shown at 01:36 in Trophy Tom’s video. Image: Auroch Digital

Purity Seal: Two skulls by the second yellow door

The level’s only Purity Seal sits outside the second yellow door [Ψ]. Two paths lead out of the purge area to two different yellow doors, and you need the one on the right.

After clearing the purge, leave the area along the right-hand path toward the second yellow door. Do not take the left path, which leads to the wrong door.

Near the door, find the two hidden skulls over the chasm. One sits above the door switch, and the other is high up on the opposite side from the switch. Shoot both.

A platform forms, giving you access to the alcove in the wall. Take the Purity Seal; YOU DISCOVERED A PURITY SEAL! appears, and the Seal counter reads 1/1.

Seal 1/1 Location & Demonstration — Shooting both hidden skulls raises a platform to the alcove that holds the Purity Seal. Shown at 02:33 in Trophy Tom’s video. Image: Auroch Digital

Secret 4: Infinite Ammo in the final arena

The last Secret is inside the large open arena past the second yellow door [Ψ]. Entering the hall starts a fight against Deranged Cultists and Bloodletters, and the floor in the side room opens up on a timer, so you have to be fast.

Push into the big hall and deal with the enemies as a small room opens on the right side.

Find the skull inside that side room and shoot it quickly before the floor drops out.

Grab the Infinite Ammo pickup it reveals. The SECRET DISCOVERED prompt appears and the counter finishes at Secrets 4/4.

The floor in this room can open beneath you at any moment, so grab the pickup and move before it gives way.

With all four Secrets registered and the Purity Seal in hand, every collectible on Blood Cascade is accounted for and you can press on toward the next mission with nothing left behind.