I’ve been playing Slay the Spire – a deck-building card game on Steam – since it was gifted to me (thanks Janne!) before Christmas. I tend to shy away from, or get bored quickly, of online card games – but this has really taken my fancy. As it went into full release this week, I thought I’d give it a plug (and there are plans to release it on Nintendo Switch later in the year, if you’re into such new-fangled gadgetry).

This is a single-player, rogue-like, fantasy-themed deck-builder. You’re an adventurer trying to defeat the residents of an ominous tower, attempting to explore through around 50 locations on your way to facing the big boss. A full run will take about two hours, but don’t expect that on your first few plays – and you can save a run anytime and come back to it later (even if it is a daily map – see below).

Each location will either be a battle (50% or more), random encounter, merchant or camp. Camp lets you rest and regain health or, if you’re doing OK, you can skip that sissy stuff and upgrade one of your cards. The merchant lets you buy/sell cards, alongside picking up potions (one-shot effects) and artefacts (permanent benefits).

One of Slay the Spire’s strengths is its world. You won’t find typical tired fantasy tropes here: both the character/deck classes (there are currently three) and the creatures you face are unique, with an art style leaning strongly towards the strange and surreal – while also being cartoony and fun. Nowhere is this highlighted better than random encounters. These are meetings with weird and wonderful creatures and devices, which can often help but sometimes hinder your progress. Some offer push-your-luck situations, others trade-offs, but they’re always well written and beautifully illustrated.

But without a good deck-building/combat system, all this would be for nought – and Slay the Spire delivers. You usually start with a 15-card deck, drawing 5 cards per turn (discarding any you don’t use). Most cost 0-3 power to use, and you start each turn with 3 (again, losing any you don’t use). Basic cards tend to either give armour for the round, or deal damage – but that really is just the tip of the iceberg. Each of the game’s three character types has a unique trait which shapes its style, but within each there are many more directions in which to try and mould your deck.

These deck-building decisions are often influenced by artefacts you pick up as you go. Perhaps one rewards you for going through your deck a lot (time to start thinning!); or lets you get extra power each round (suddenly those power-hungry cards you were ignoring look more tempting). Add in a plethora of crazy creatures with every kind of special ability you can think of, from special damage types to loads of temporary and long-term effects, and it really does have it all.

But of course, this is a rogue-like game. At the end of your run, win or lose, you start next time with the basics (although on most runs you’ll unlock new artefacts and cards that will now be available next time) – or do you? One of my favourite aspects of the game are daily runs. Every day, a weird random combo of starting effects is put together and everyone can see how they cope with it. Maybe you start with 50 cards, or draft your deck, or have one of each rare card; maybe you lose max 1HP per round, or start with three artefacts, of can’t upgrade cards. It means every day has a unique challenge – and yes, there is a score board to see how you’re doing against your peers.

But I’m going to leave it here, simply because one of the real joys of Slay the Spire is discovering all its strange delights for yourself. The game is less than £20, has ‘overwhelmingly positive’ (96% at time of writing) reviews on Steam, and is comfortably the best casual single-player card game I’ve played on PC.