Nightmare Reaper’s procedurally generated stages are as rawly aggressive as the thrash metal motifs that drive it. Coined a looter-shooter, it’s a roguelite that revels in retro visuals, blazing speeds, and the ensuing spectacle of its bloodbath.

In a novel move, it procedurally generates levels, meaning each time you die or start over, things have changed. The aesthetic alters by chapter, shifting from watery pits and spiky tombs to hospital wards and cities; and, if you can find them, space stations where pets can be purchased that help you uncover secrets. The layouts are mostly unique with each new playthrough, but hitting switches, finding keys, or locating suspicious walls to kick through is a constant. At its best, the procedural element generates levels that feel deliberate, which is impressive considering its layering. That said, it’s not perfect, with sections occasionally recycling, dead ends cropping up, and on one occasion, an impassable early jump that forced us to quit the stage.

Nightmare Reaper is stuffed to bursting with content. Upgrades, buffs, rebuffs, and all that jazz. There are secrets and power-ups everywhere, droves of enemy types, and 80+ weapons to seize, all with modifier possibilities, allowing you to ice up the undead or turn an entire arena into a blazing inferno. You can choose one weapon to carry over to the following stage, and the looting-progression element encourages you to reap gold and find hidden rooms littered with treasure. By acquiring new in-game game cartridges, you get new skill trees on a GameBoy Advance SP sub-screen, which can be accessed at any time for a mountain of purchasable upgrades. When acquiring a new skill, you get to play a rudimentary 2D stage that mimics the likes of Gradius or Super Mario Bros. 3.

The gunplay is knee-deep in bones and blood, coupling dry humour with ultra-violence, and painting the screen all kinds of pixellated crimson. It doesn’t achieve the same feedback as something like Brutal Doom, but it does spew dense, spectacular hordes for you to carve into pieces. The music is great, with DOOM Eternal’s Andrew Hulshult summoning a predictable but perfectly applied set of metal tracks, complete with thundering drums and deathly riffs. The controls, too, are well-conceived and straightforward.

There are a few caveats, however. In addition to the procedural element occasionally coming up short, the main campaign is arguably too bloated at around 90 levels and can become exhausting under the weight of all its bounty. Sometimes, too, its pixellated rendering can be confusing, especially when you’re searching for switches or keys; and many of the secret rooms or items aren’t often useful or worth seeking out. The story aspect, which puts you in the shoes of a female patient on a hospital psych ward, slipping in and out of nightmare worlds, is fairly interesting, but having to return to your hospital room between each stage for minor aesthetic changes or a new page of a doctor’s journal quickly wears thin.

Nightmare Reaper does, however, achieve most of what it sets out to do, pushing boundaries in terms of weaponry, spectacular abilities, and more trinkets than a fully loaded cargo ship. It’s at its best when it devolves into a spectacular bloodbath at the whims of your creative weapon and ability choices. And, while imperfections exist, its violent, adrenaline-fuelled highs will make it very appealing to fans of the old-school FPS.