Castle in the Darkness is a game that had a strange effect on me. After a couple hours playing I suddenly felt determined to finish it. There are many challenges on the way to find the missing princess and the difficulty, and sometimes frustrations, are extreme in places but I was hooked. Seven and a half hours after the adventure began, the credits rolled and I sighed a sigh of relief.

This is a 2d platforming 'metroidvania' game with a retro aesthetic. It wastes no time in putting you in action. After a brief introduction sequence which contextualises the narrative – a princess goes off on her own in search of her missing father – you are not playing long before facing the first boss. Things start off without much challenge but ramps up considerably.

Checkpoints are scattered across the land and occasionally feel few and far between. You have a small amount of health at the beginning of the game and you'll die a lot. A lot. Several hits from an enemy and you're dead or a single hit from a spike; either along the ground or falling from above. However, this is a game that doesn't cheat you. It is your own fault that you die, not the game messing you around. There were many points that I found myself stuck but I kept at it and was finally able to progress. Happily, it doesn't take long to restart after you die. The screen flashes red and shows you the death-count, then pushing right will spawn you at the last checkpoint.

The challenge of the game is one of the most rewarding aspects. There are a number of times when backtracking is required (though this isn't necessarily essential, but you'll have a much harder time going forwards if you don't). As you don't gain access to warp points til over halfway through the game you just go through the game backwards. It is with these moments you realise how much you've improved; as you go through areas you previously had great difficulty with without problem.

The jumps require precision, spike traps demand your attention as you move through an area and learning the enemy patterns is a must. As you go to your sixth or seventh screen without a checkpoint in sight the pressure ramps up. There are no health potions in the game. Your health gets refilled at every checkpoint. The frustration in having to repeat the same screens many times because of one bit later on that you struggle with is great and could lead some plays to give up on the game. Not me though, it just made me more determined.

Progression is constant. You can equip armour and weapons, find relics each with their own power and use one spell at a time. There are also items you find; keys to new areas and health bonuses. Defeating each of the many bosses grants you plus one health. Some of the relics are hard to find but absolutely worth it. They include: a double jump, the ability to swim and walk on ice without slipping. They make a big difference to how the game plays. I ended with the penultimate sword, just four spells and half the armours in the game.

As you play through Castle in the Darkness you'll notice locked doors and areas that you can't reach. This is where the backtracking comes in. As soon as I got the double jump (a power I was anticipating considering what I'd seen on my way) I went back and found all the secret areas I could. The lack of a map doesn't have an impact; the world design is tight and you become familiar with it swiftly.

The aesthetic design of each area is strong and varied and the enemy designs are fantastic. There are many boss battles throughout the game and every one of them is designed well. They pose a lesser challenge though. Learn their move routine and you'll beat them all without taking too much damage.

I found an interesting dynamic with the game's difficulty too. There was one area later on in the game – the windy ruins – that I really struggled with. It was a simple jump against the wind but I just couldn't make it. It turned out I had equipped heavy armour and it was decreasing the amount I could jump. It took me ages to figure that out; entirely my own fault. No other armours had an effect on the character but it did say in the description. If only I'd paid attention. Another moment was a boss fight I was struggling with. I decided to try my luck and jump over him and attack from behind. He didn't turn around and continued his attacks to the left of the screen while I used magic attacks behind him. It was a satisfying moment.

The chiptune soundtrack is absolutely fantastic throughout the game. It keeps you pumped and lessens the blues of the frequent deaths. There are great tonal shifts in the tracks which mirror what you are currently experiencing. You can buy it for about £1.80 on Bandcamp.

Castle in the Darkness is tremendous value for money. It took me just under seven and a half hours to complete (with only 58% completion) and it only costs £4.79. I ended up with just under three hundred deaths. This is a game I wholeheartedly recommend. It was an engrossing, addictive and, above all, fun experience.