Sublevel Zero Redux Review

By Sam Quirke, 2 years ago
Imitation can be the greatest form of flattery. Sigtrap Games have stated their fondness for 1995's Descent and 1998's Forsaken and saw an opportunity to revive the mostly dormant "six degrees of freedom" FPS sub-genre for modern audiences, borrowing pretty heavily from those that went before. 6DOF shooters also allow the player to pitch, yaw and roll on top of the traditional planes of movement. This can lead to some mind-bending perspective shifts as you adjust your orientation. It's certainly a rare framework for a corridor-based FPS, and with Sublevel Zero Redux Sigtrap have attempted to carve an even more innovative niche by fusing the core gameplay with rogue-like elements. The resulting experience is uniquely compelling, in spite of a few flaws.


The game’s story is minimalistic, limited to text-based scene setting at the beginning and a paragraph or two at the finish. Ultimately this is window dressing to put the game in context, but that’s no bad thing. You’ll work through a level in your craft, zapping enemies as you go, until you reach and destroy the core to move onto the next.

Each time you start the game you will be facing levels of a similar tone and difficulty but the actual structure, enemies and collectibles will be different, with only the attack patterns of each level’s core staying the same. Procedural generation is a perfect fit for 6DOF exploration. The additional planes of movement beyond a normal first-person shooter are both confusing and a little thrilling, so adding randomised level layouts on top of that really gives you a sense of exploring unknown territory in deep space that even blockbuster sci-fi titles often fail to grasp. At the same time, using archetypes of the genre give players an anchor of familiarity — despite the disorienting levels, you’ll still find trapped treasure rooms and colour-coded keys to matching doors. The map screen is also well-conceived, managing to both accentuate the feeling of inertia and provide you with an oasis of calm in which to get your bearings. The 6DOF controls can be a little cumbersome on the default mapping, and while there are a variety of alternative options in the menu, a game that needs this much movement precision really needs to offer full mapping customisation.


There is a rudimentary crafting system in the game in order to further change up your play experience, with the ability to change up your two gun slots and two ammo slots with a variety of weapons. You can also trade out your hull and engine with something more beneficial. It’s a little too simplified for my taste, basically amounting to combining two weapons, hulls or engines together in order to make something new. Options for new constructions seem limited, and I spent large chunks of each play-through lugging around unused items because none of them combined into anything. You gradually pick up new crafting instructions as you replay the game, but it’s a little too slow in arriving for a relatively short-lived experience.

Using the guns and cannons themselves is pretty fun. Each weapon type has a range of options and efficacies, and it truly changes your approach. If you run out of ammo and find yourself having to change weapons mid-fight, it really feels like you have to adapt to a different mode of play. You’ll need to manage your inventory carefully and stay stocked up on health kits. Using these generates HP painfully slowly — if you’re under a lot of fire, it might not be quick enough to save you. With the threat of permadeath hanging over you, it’s a wonderfully tense experience that only gets more nail-biting as you work through each level.


Some elements of the game are nail-biting for the wrong reasons. Crucially, the pickups that spray out of downed enemies look very similar to distant enemies. If you cause a chain of enemy deaths in a packed room, it becomes pretty difficult to tell what to shoot at. The voxel-esque art style is highly appropriate and even pretty at times, but it also means that you get blocky white haze covering the screen when explosions start kicking off, especially towards the end of a stage. This is a hazard in many games, but with the disorientation of 6DOF movement and procedural generation already playing against you it feels a little much. I even came across considerable framerate lag when enemy fire was at its most dense, with the game grinding to a complete halt for thirty seconds during a difficult boss fight. Thankfully lag of this intensity has only occurred a couple of times, but it’s the last thing you want to be paranoid about when you’re already feeling tense.

These issues may turn some players off, but in some ways they are alleviated by the game's short length and the ease with which you can get back into the action. It won’t take too long to rip through the first few levels once you are used to them, and with randomised enemies there's always a chance that your next run will be significantly easier than the last. I was struggling to get through the campaign on easy mode to start with, but during a lucky run with fewer difficult enemies I also received the materials to craft a hull with a high HP, giving me a window of opportunity to make it through to the finish. The game certainly nails that “just one more turn” feeling that makes the best rogue-likes so appealing, even if it’s ultimately a little short and simple compared to a lot of its contemporaries. Three difficulty modes with alternate levels give you a good reason to return, making a substantial difference to enemy attacks and damage resistance.


The audio design is a treat to the ears if you like your nostalgia served with modern sensibilities. The title menu theme is a superbly catchy homage to 8-bit sci-fi reimagined as an airy synth track, and the music in game is suitably atmospheric without being intrusive. Every sound effect seems lovingly crafted with an ear for nostalgia, despite using modern instrumentation. Visually the game is quite mesmerising between the neo-industrial architecture and the pixelated pyrotechnics, though it’s best viewed from a distance — some of the wall textures are pretty poorly rendered even when the pixel art style is taken into account. The only other visual hiccup is the text and menu design. The writing is at times nearly illegible on the default view, particularly when you pick up a facility log. Luckily you can change the width of your field of view in the Options screen, but if you prefer to have a wider lens when exploring the facility you may find yourself struggling to read anything. On top of this, the menu structures are really odd with multiple scrollbars and tabs that are clunky to highlight with the thumbstick. It’s a shame that these design hiccups are so distracting, because behind the irritations is a genuinely compelling shooter offering something really unique.

The achievement list is a decent blend that helps you explore everything the game has to offer. You’ll find achievements for finishing the campaign in a number of different ways, whether that’s crafting a lot, not crafting at all, or avoiding the use of certain weapon types. Getting through the first three levels with no damage will also earn you some gamerscore. The biggest challenges will likely be finishing the game with the final hard levels unlocked, and nabbing the randomly generated facility logs — several of which will only appear in later levels. This reviewer will certainly be returning to take on the challenge.


Sublevel Zero Redux is one of the standout shooters in the indie scene. Fusing "six degrees of freedom" shooting with permadeath, procedural generation, and crafting makes for a tense and unpredictable adventure each time you play. The rogue-like elements are enhanced by the tension of a traditional corridor first-person shooter, though it might feel a little simplistic to genre veterans. Some odd design decisions are a little frustrating, especially when they conspire against you in the game's more intense moments. If you can see past the game's hiccups, you will find a compelling and unusual experience that teases you into one last try with every Game Over.
4 / 5
Sublevel Zero Redux
  • A welcome return of the niche "six degrees of freedom" FPS
  • Rogue-like procedural maps and permadeath add depth and tension
  • Nails the "just one more try" feeling
  • Excellent retro-inspired audio
  • Some visual design problems and instances of lag
  • Menus are oddly structured and confusing
  • Deeper crafting trees would have been appreciated
Ethics Statement
The reviewer spent five hours bouncing off the walls and forgetting which way was up, earning 14 of the game's 27 achievements. An Xbox One digital code was provided for the purposes of this review.
Please read our Review and Ethics Statement for more information.
Sam Quirke
Written by Sam Quirke
Sam has been a Newshound since 2016 and is now the Editor for both TrueAchievements and TrueTrophies. He loves gaming on all devices and in all genres. He remains a stubborn Assassin's Creed and Pokémon fan.