Hardest Bosses in Slay The Spire 2 Ranked

Climbing the Spire, you’ll die, over and over again. Sometimes to normal enemies who stand in your way, sometimes to strange events that befall you, but most of the time, you’ll die to a boss that lies at the summit of each Act.

Did you go in at half health? Did you choose too many events and fail to pick up the necessary cards? Were you playing too riskily? Whatever the reason, the bosses of Slay the Spire 2 are not to be trifled with.

As you rise up the Ascension ranks, you’ll need to play smart and path wisely, or these bosses will send you right back to the start. Today, let’s take a look at some of the most difficult bosses and just how to prepare for them.

12 The Kin

3 Against 1? No Problem.

Who knew 3 enemies would be easier than 1? It can be a bit intimidating the first time you come face-to-face with The Kin, especially if it’s one of your first times climbing the spire.

However, this is easily the weakest boss in all of Slay The Spire 2. You have 2 ways to go about this fight. You can either take out the minions, leaving the leader all alone, or if you have a nice amount of burst damage, you can simply target the leader. Once the leader dies, all minions immediately perish with them.

None of these enemies really deal that much damage, and the minions fall very quickly. Either way you choose, as long as you go in with a decent amount of HP, you’ll be fine.

11 Lagavulin Matriarch

Deja Vu!

Anybody who has played Slay the Spire 1 will remember a certain Elite version of this enemy. One who, in my opinion, was actually harder than the boss version.

The Matriarch has a decent amount of health and can put up a good amount of Block, but you have the advantage here. The fight will begin with the boss asleep. You get pretty much 3 free turns to set up your deck before the boss finally awakens.

Whether you simply wait for the perfect hand to deal a good amount of damage or set up as many powers as possible, making good use of those free turns is crucial here. If you manage to get a lot done with those turns, this fight will be a walk in the park.

10 Soul Fysh

The Eye is the Window to the Soul

Soul Fysh has a couple of mechanics that can be tricky at times, but it very much depends on what kind of deck you’re running.

The first thing you’ll notice is the Beckon status cards that the Fysh adds to your hand. You can either play these to avoid 6 damage or simply discard them. Every deck has access to a decent amount of discard or exhaust mechanics, especially the Silent and the Ironclad. If you find a way to get rid of these status cards, it’s almost as if the mechanic never existed.

In addition, occasionally the Soul Fysh will become Intangible, meaning it will only take 1 damage at a time. This really isn’t a big deal, as you can simply focus on blocking. This boss doesn’t really have any difficult attacks to dodge; it’s more about chip damage over time. A good amount of discard or block solves this issue.

9 Kaiser Crab

That’s right, I’m not just listing Act 1 bosses at the bottom here. Kaiser Crab looks pretty threatening, that’s for sure. However, anyone who has played Act 4 of Slay the Spire 1 and faced the double enemies before the Heart will find this fight to be a piece of cake.

This crab needs to be fought in 2 directions, left and right. If you’re facing towards a certain arm, that attack will be decreased as long as you face it. This boss has some pretty powerful attacks, including its rocket claw, but you can control the ebb and flow of the combat by choosing your direction.

With a decent number of blocking cards and a way to inflict Weak on your opponents, this fight is no issue.

8 Ceremonial Beast

Xerneas, Is That You?

The Ceremonial Beast can often be an issue, as it has a little bit of everything. Not only does this funky-looking deer have a solid amount of health, but it has ramping damage and a way to limit your turns.

You can’t afford to set up for too long with this boss, as you’ll quickly fall to the Beasts' constantly increasing attacks in the first phase.

And even if you have a good amount of burst, once you hit the 2nd phase, certain attacks will inflict Ringing, which means you can only play 1 card during that turn. Not only does this pretty much force you to take damage, but stops combo decks from working their magic. For Act 1, this is certainly a tricky boss to fight.

7 Vantom

This is One Slippery Fellow

Vantom is a very predictable boss, as it will always follow a set 3-attack pattern, stretching out its tail to slash down on you from above.

That final blade attack can be pretty rough, but that’s not what makes this boss so tricky. Vantom starts out with Slippery, which is basically Intangible with 9 charges. You have to attack his boss 9 times before you can actually start dealing any damage.

For certain builds, with multi-hit attacks, or lots of orbs, this is no big deal, but if you’re running a deck that deals in high-cost slow attacks, this can be a real pain. By the time you’ve removed his buff, you’ve probably already gotten hit by the big Dismember attack, and now your deck is clogged with wounds, meaning your next draws will be even worse.

6 The Doormaker

All Bark and no Bite!

An Act 3 boss so low down on the list? I know it sounds strange, but in its current state, Doormakeris ridiculously easy compared to its other Act 3 counterparts.

In reality, this boss is just a huge HP pool, amounting to more of a DPS check than anything else. If you have a decent amount of burst damage, you won’t need to see the Doormaker’s face more than 1 or 2 times max.

What's more, the boss keeps its debuffs even when it returns, so it’s still viable to run Poison and Doom builds against it. It’s an interesting design, but certainly not as challenging as the other 2.

5 The Insatiable

Arrakis Wants Its Worms Back!

This was the first Act 2 boss I ever saw, and at first it terrified me. A massive sandworm capable of taking you down in 1 shot? Ouch!

However, with proper energy management, this boss is really not that big of a deal. The insatiable gifts you a bunch of status cards, which allow you to escape being sucked towards its sinkhole. These increase in energy every time you play them, but they are crucial if you want to stay alive.

The thing is, this boss doesn’t really have any particularly hard-hitting attacks, so all you need to do is play normally, while threading a couple of Frantic Escapes into your turn. If you have ways to generate more energy and debuff this big worm, you’ll be fine.

4 Waterfall Giant

It’s Not Over, ‘til it's Over!

This is easily my most hated Act 1 boss, and for good reason. Perhaps it’s my fault for the way I like to play, but most of my high-Ascension Act 1 losses are to this guy.

Waterfall Giant pretty much requires you to be on high HP when you enter the fight, which is something I often struggle with. As they say, the only important health point is your last, so I like to upgrade my cards at rest points whenever I can and play a bit riskily.

Waterfall Giant doesn’t have any particularly devastating attacks… apart from its last. Over the course of the fight, it builds up steam for an eruption. After you’ve taken it down, it will self-destruct, dealing damage to you equal to that Steam Eruption counter. This can easily reach anywhere from 30 to 40 damage. You can try to block this, but if you're already on low health, well… you’re toast!

3 Test Subject

Back to the Lab with you, Beast!

This fight is tricky in many regards. Test Subject has 3 phases, each with 100 more hit points than the last, for a total of 600 HP. However, unlike the Doormaker, the next phase counts as a new entity, meaning any debuffs you’ve applied will go away. Already, this makes the fight more of a pain.

Now, when you add on Enrage, Painful Stabs and, of course, Intangible, this boss fight becomes a real pain. In its third phase, if you don’t have a good way to defend yourself during the intangible phase, you’ll die extremely fast. In addition, if you draw all your attacking cards on the wrong cycle, you’re also screwed.

This requires you to have a good amount of draw-cards in your deck, as well as energy generation to keep your turn going. Without these, you’ll have a huge number of dead turns, and your run will be over before you can even blink.