Warhammer 40,000: Boltgun is an unexpected but welcome addition to the many video games of the Warhammer 40k franchise, having elements that many would call old school, but that is the point. It takes after retro-shooters popular in the 90s, chiefly the infamously gruesome and awesome original Doom. Everything from the graphics to the gameplay takes inspiration from this era of video games and unites them with the futuristic grim darkness of Warhammer 40k, granting Warhammer 40,000: Boltgun the best of both worlds.
Of the many inclusions from retro-shooters, by far the most iconic implemented into Warhammer 40,000: Boltgun is Secrets — hidden away boons that help players on a mission. Such Secrets include Relics and Special Ammo, which enhance the player and give their Boltgun powerful ammunition, respectively. The effectiveness of these Secrets cannot be stated enough, making them a priority for players if they wish to overcome challenging missions. So, here is every Secret in Chapter 1, Missions 5-8.
Mission Five: Martyrs Crossing (Secrets - Seven)
Secret One - Machine Spirit
To find Secret One of Mission Five, players must head straight ahead from where they started, pushing forward until they arrive at an area with two pillars ahead and a bridge to the right.
From here, they will head left until they reach a snowy cliffside cluttered by pillars. Initially, players will see nothing but a long fall down.
If they round the corner to their left, however, they will find an open crate containing the Machine Spirit Relic. This powerup grants the weapon held by the player an upgrade unique to it. Regardless of the armament they choose, it will undoubtedly become a killing machine with the Machine Spirit.
Secret Two - Assault Doctrine
To find Secret Two of Mission Five, players must progress through the mission until they reach a button door with a Plasma Gun and Plasma Rounds to their right.
Immediately upon passing through the door, players are met by an area cluttered with crates, sandbags, and supplies with large metal fences flanking the sides.
Players will see two open crates ahead and must approach the one to the left. Inside is the Assault Doctrine Relic, a devastating powerup that empowers the player's Chainsword, making it much better at ripping and tearing through enemies — something it is already great at doing.
Secret Three - Vengeance Rounds
Secret Three of Mission 5 lies nearby, but players must head straight to the end of the fenced area, where they will find a button door to their left revealing a room. In the room, players will discover various enemies protecting the Red Key. They must eliminate them and collect the key.
Upon doing so, players must head across from the button door they opened before; they will find the Red Door on the right end of the fenced area.
Using the Red Key, they can open the Red Door, unveiling a small room where Vengeance Rounds lie straight ahead. This potent Special Ammo allows the Boltgun's bullets to penetrate surfaces and enemies, turning an already powerful weapon into an implement of untold carnage.
Secret Four - Vortex Grenade
For Secret Four of Mission Five, players must continue their mission until they take an elevator up to a room with cultists, daemons, and a Chaos banner.
They will move past this room to the corner hallway leading outside. Players will stop here and investigate the blank and seemingly unimportant wall to their left.
Approaching the wall reveals an interaction option, which will cause the wall to open, uncovering a small section where the Vortex Grenade Relic lies. This explosive is unlike any other, as it uses the cataclysmic power of the Warp to shred nearby enemies.
Secret Five - Infinite Ammo
Secret Five of Mission Five is a ways ahead, meaning that players will have to progress until they arrive in another messy area flanked by impressive fences; however, this space differs from the last in that it has a bridge overlooking the center.
Players must venture to the center of this bridge, where they will find the Heavy Bolter. They must grab it, which will initiate a Purge Protocol and be assaulted by a wave of Screamers of Tzeentch.
After dispatching this wave of daemons, a door to the left of where the Heavy Bolter was will open, revealing a small alcove.
Players will find the Infinite Ammo Relic inside. This powerup does as the name suggests, granting the player endless ammunition for a short duration.
Secret Six - Munitions Boon
Finding Secret Six of Mission Five requires players to push ahead until they descend an elevator to a room cluttered with crates and a doorway to the left leading outside.
Players will find the Munitions Boon by heading straight ahead to the open crate and looking inside. This powerup increases the ammo capacity of the player's weapons.
Secret Seven - Kraken Rounds
Secret Seven, the last Secret of Mission Five, requires players to progress until they happen across an area with hanging gantries — platforms precariously held up by chains.
They must head to the center platform, which lies under an overpass between two massive supports for the structure above.
On this central hanging gantry, players will find Kraken Rounds — Special Ammo with the unique property of shooting faster than normal Boltgun bullets.
Mission Six: Venerable Bastion (Secrets - Seven)
Secret One - Machine Spirit
Secret One of Mission Six can be found shortly after starting the mission; all players must do is progress until they reach the area with a system of pipes overhead.
From here, they must go towards the snowy edge on the left and look for an open crate ahead.
Players must reach the open crate by jumping across the gap to it. Within, they will find the Machine Spirit Relic.
Secret Two - Munitions Boon
Secret Two of Mission Six demands players keep on with the mission for some time until they come to a point where they are overlooking an area crowded with crates and tainted by Chaos. They must be careful not to drop down to this space, or they will miss the Secret.
From the point where players overlook the area, they can spot an edge ahead of them splattered with yellow paint. They must leap across and clamber up the edge.
Up ahead, players will find the Munitions Boon Relic in front of an Adeptus Mechanicus banner.
Secret Three - Vengeance Rounds
Secret Three of Mission Six requires players to progress until they find the lock for the Red Door.
From here, they will follow the bridge to their right.
After crossing, players will look to the right, seeing an area tainted by Chaos and a crate.
Players must hop on top of this crate and look to their left, where they will see a ledge they can jump to and climb up.
Atop this ledge to the right, players will find Vengeance Rounds.
Secret Four - Vortex Grenade
To find Secret Four of Mission Six, players must push forward until they happen upon a bridge leading to a wall with cone spikes protruding from columns.
Players will not continue on but instead hop onto the short wall to their right and look around the corner. They will see a snowy ledge across from them.
Carefully, players must leap to the edge of this cliff and clamber up. They will find a room secluded away to their left.
Within this room, near banners of the Adeptus Mechanicus, players will find the Vortex Grenade Relic.
Secret Five - Emperor's Visage
Secret Five of Mission Six is nearby. Players must continue forth until they come across an area tainted by Chaos, where the Yellow Key resides.
They must head to the wall directly ahead and look to their right, where they will see a slanted roof within the distance.
Players must jump to this roof and clamber to the other side before dropping down to the floor below.
From this position, players can spot a bridge below across from them.
Leaping to this bridge will bring players to the Emperor's Visage Relic, which is to their immediate right.
Secret Six - Kraken Rounds
For Secret Six of Mission Six, players must open the Yellow Door with the Yellow Key.
They must then enter and round the corner to their left, bringing them to a small room with a blank wall to the left and a doorway to the right.
Approaching the empty wall to the left allows players to interact with it and open it as if it were a door, revealing a small area where Kraken Rounds can be found.
Secret Seven - Aura Of Doom
Secret Seven, the last Secret of Mission Six, can be found in the final area of the mission. After exiting the elevator, players must go to the left.
There, they will find a path to the left and a doorway straight ahead. Players must take the way to the left.
Following the path brings players to a ledge splattered with yellow paint. They must clamber atop this ledge and look toward their right.
Players will see a crate and yet another ledge above splattered with yellow paint. They must climb up the container and to the yellow-painted edge, then look to their left.
At first glance, players will see nothing more than some barricades and a crate way in the back, but they should approach the crate, which they will find is open.
Within the open container is the Aura of Doom Relic.
Mission Seven: Forbidden Knowledge (Secrets - Six)
Secret One - Kraken Rounds
Secret One of Mission Seven demands players to go through the missions normally until they come across a staircase descending to a room defiled by Chaos.
Upon entering the room, players will find an area ahead with crates stacked atop each other.
They must approach these containers from the right, revealing that the crate on the ground closest to the wall is open.
Within this open container, players can find Kraken Rounds.
Secret Two - Machine Spirit
From here, players must progress to find Secret Two of Mission Seven until they find a room with a banner of Tzeentch and the Red Key.
Players will find seemingly ordinary clutter to their left, but moving forward and looking to their left will reveal an open crate.
Looking inside this large container, they will find the Machine Spirit Relic.
Secret Three - Vortex Grenade
Secret Three of Mission Seven requires players to move forward until they find a large elevator.
Taking it up will bring players to a space complete with various containers and materials of war, but they must focus on the open crate ahead.
Approaching the crate and looking within reveals it to be open on both sides, leading to a secluded area.
Following the open crate to this nook brings players to another open container, and within is the Vortex Grenade Relic.
Secret Four - Emperor's Visage
Secret Four of Mission Seven is not far from here; players need only continue a bit further until they come across a banner of Tzeentch.
Players will find a button door to the left of the banner, but they must ignore it and instead turn their attention to the crates on the right.
A closer investigation reveals that the top container is open, and players can reach it by clambering up.
Climbing into the open crate reveals the Emperor's Visage Relic within.
Secret Five - Munitions Boon
Players must continue on for a while before coming near Secret Five of Mission Seven. Eventually, they will happen upon an area blockaded by crates, with one in the middle open on both sides.
After passing through this container, players must look to their left, where they will find a ramp.
Going up this ramp and looking ahead will face players with an empty wall, seemingly ordinary in every sense of the word.
However, approaching it reveals an interaction, which will raise the wall, revealing a small room with the Munitions Boon Relic.
Secret Six - Assault Doctrine
Secret Six, the final Secret of Mission Seven, lies in the last area before players conclude the level.
To the right of where players enter this space is a hole in the ground, descending to a lower level.
This path leads players to a library; they must not delve further into the library but rather go to the bookshelf on their left, around the corner.
Players will find a seemingly normal bookshelf but with an interaction option.
Interacting with the bookshelf will cause it to slide across the floor, revealing a small alcove with the Assault Doctrine Relic.
Mission Eight: Sanctum Magistrum (Secrets - Six)
Secret One - Munitions Boon
Secret One of Mission Eight lies near the area made foul by Chaos, where players will face various daemons.
To the right of this space, players will see a staircase leading to a level above.
Rather than follow the staircase up, they must follow the path on their current level winding around towards the right.
Following it to its end brings players to the Munitions Boon Relic.
Secret Two - Vortex Grenade
Secret Two of Mission Eight will take players to a tall tower with an ominous pillar decorating its interior.
They will go up the tower until they reach the first level doorway, which leads to a room with a Heavy Bolter.
Entering the room will bring players to two doorways leading outside, but they should ignore the one on the right.
Going through the left doorway will bring players to a bridge leading to the right.
Following the bridge to its end brings players to the Vortex Grenade Relic.
Secret Three - Machine Spirit
Secret Three of Mission Eight lies near the same tower players are in. All they must do is follow the ramp to the uppermost level, where there is seemingly nothing beyond a balcony.
However, should players follow the balcony to the right, they will see an area below they can leap to.
Dropping into this space brings players to a building separated from the tower.
Within the structure, players will find a bloody mess surrounding the Machine Spirit Relic.
Secret Four - Dragonfire Rounds
Secret Four of Mission Eight is close by, as players need only to traverse through the Warp portal into a room corrupted by Chaos.
To the right of the room, players will find a smooth and empty wall that seems nothing extraordinary.
Approaching this wall will reveal an interaction that causes it to shift open, revealing a room with Dragonfire Rounds, a type of Special Ammo that sets enemies ablaze for a fiery death.
Secret Five - Kraken Rounds
Secret Five of Mission Eight is tricky, as players must progress to an area complete with various Warp portals with unpredictable exit points that bend reality.
Players must go straight forward upon arriving until they come across a divide leading to two portals.
Players must follow the right path and enter the portal.
This gateway will take them to a bridge leading straight to yet another portal, which they will go through.
Passing through this portal leads them to a bridge leading to another, which they will also pass through.
Players will be spit out to yet another bridge with a portal ahead, but they will not pass through it. Instead, they will go to the left edge of the bridge near the two massive columns.
Hopping on the wall and looking down, players will see the underside of a bridge, which they will hop down to.
From where they land, players must move forward to the arch marked with a symbol of Chaos.
Players will find the Kraken Rounds by jumping atop the arch and looking down.
Secret Six - Aura Of Doom
Secret Six of Mission Eight, the last Secret, requires players to reach the final area where a massive concentration of Chaos exists in the center.
They must head to the edge in front of them and drop down to the floor on their right.
Doing so brings players in front of a Warp portal, which they will travel through.
Going through brings them to an ascending walkway they must follow up.
Players will reach a platform that continues on to another Warp portal, but they will not proceed further.
Instead, they will look to their right toward a floating mass across. Players must leap to this afloat structure.
On it, they will find the Aura of Doom Relic, which will prove beneficial for the boss fight occurring in this area.
Warhammer 40,000: Boltgun is available for PC, PS4, PS5, Switch, Xbox One, and Xbox Series X.