While the developers of Castle of Heart have done little to encourage it, it's easy to see why this Switch eShop release is being dubbed "the Dark Souls of platformers" by some in the Nintendo community. It boasts a very similar medieval aesthetic to the beloved Souls series and contains gameplay that is often punishing and infuriating; however, it doesn't quite match up to FormSoftware's sadistic masterpiece in terms of balance and nuance, and the end result is an action title that is only likely to entertain those with incredibly high thresholds for frustration.

Placed in the boots of a brave knight who has been turned into stone, Castle of Heart is a 2.5D platformer which sees you stalking through abandoned villages and ruined fortresses with the aim of rescuing your sweetheart and putting an end to the malevolent plans of an evil sorcerer. Your troubling affliction serves as a way of ratcheting up the tension; health slowly depletes as your character crumbles to dust, and it's only by collecting health icons (which are dotted around the landscape and dropped by fallen enemies) or passing through a checkpoint that you can restore your vanishing vitality. This curse is reflected in other ways, too; should your health drop below a certain point you lose one of your arms, which predictably limits your combat options.

Speaking of combat, you have a few choices available to you when it comes to dealing with the many antagonists standing in your path. Melee attacks with your sword are fine for dealing with enemies in close proximity, but one-on-one battles rarely end without you taking some damage – and when you consider how delicate your health situation is, that's not always a welcome scenario. Thankfully, you can collect various limited-use ranged weapons – such as spears, crossbows and knives – which allow you to keep foes at a comfortable distance. The downside to this approach is that some enemies also have ranged attacks, and its during these stand-offs that you'll want to make use of your block command. You can also perform a dodge roll which is handy for getting out of the open and into cover. Other items – such as bombs – allow you to destroy obstacles and you also have access to a powerful (but slow) sword attack that achieves much the same effect, but depletes some of your precious health.

Castle of Heart leverages pretty much every button available on Switch, and the controls do take some getting used to. Another issue is that jumping is quite floaty, and this can make judging some of the harder leaps quite difficult. Environmental features such as crates, ropes, lanterns and other objects can be used to both help and hinder progress; for example, cutting the rope of a lantern with an arrow will cause it to plummet earthwards, creating an inferno that damages nearby enemies (and you). The level design is more complex than screenshots might suggest and often you'll find there's more than one option when trying to overcome a particular choke-point. Exploring off the beaten path is always a good idea; each level has plenty of bonus items to find, including five purple gems on each stage – only when you found all of these can you consider the level truly complete.

Visually, Castle of Heart is an impressive achievement. The backgrounds are rarely less than stunning, and feature little details that stretch all the way off to the horizon. The character models are slightly less striking; while they're nicely detailed, the animation looks a little stiff and unconvincing. The audio is a similarly mixed bag; the music is neatly understated and does a good job of setting the scene, but the grunts and moans made by the game's cast become quite annoying after a while. Everything moves along a decent pace, with smooth scrolling and generally impressive effects.

While Castle of Heart clearly sees itself as an old-school action title, there are a few things that prevent it from living up to its promise. Combat is clunky and unsatisfying, despite the range of options available to the player. Enemies take multiple hits to kill with your sword, which – as we've already mentioned – makes close-quarter fights a massive risk to your health. It feels similar to the combat seen in Castlevania: Lords of Shadow - Mirror of Fate on the 3DS, but there's none of that game's clever combo work on offer here; as a result, it becomes frustrating, fast. All too often you'll find yourself surrounded by enemies – both above and below – and in some of the trickier levels, just taking a few hits means you won't be able to make it to the next checkpoint. The levels are massive and checkpoints are spread out quite thinly; expect to repeatedly play many of these sections over and over until you finally (somehow) make it through.

Dark Souls is, one could argue, a very similar proposition; you fail a lot, but it's part of the appeal. The issue is that with Dark Souls, even when you fail there's a chance to dust yourself off, spend some of your hard-earned souls and try again, blessed with more experience and better stats. In Castle of Heart, hitting a bottleneck requires you to painstakingly pick your way through that particular section, finding the right route and making sure you take as little damage as possible. On paper, this sounds like a pretty engaging cycle of risk and reward, but the issue is that it's almost impossible to avoid taking damage through your own skill. Some enemies are unavoidable, and engaging them in combat usually means taking more damage than you can heal with the resultant health item they drop. Granted, getting to the next checkpoint by the skin of your teeth is exhilarating – and there are neat little tricks to discover, like jumping onto an enemy's head and using them as a platform to escape from combat – but there's ultimately too much frustration blocking the way to give these brief moments of reward any lasting impact.

Conclusion

Castle of Heart looks great and offers a stern challenge to those who don't mind repeatedly playing the same level over and over before finally beating it and moving on. There's definitely some fun to be had finding the best route through each stage and delicately picking off enemies, but the constantly-depleting health bar and frustrating combat will have many players giving up and moving onto games which are less harmful to their general well being.