Soul Fysh is one of the final bosses of the alternate Act 1, Underdocks. It can be a nuisance to deal with, especially with its status cards, Beckon, which deal unblockable damage.
This fight in Slay the Spire 2 revolves around smart card rotation to exhaust the status cards and deal sizable damage without prolonging the encounter. Here is a complete Soul Fysh boss guide to help you reliably reach the next act.
Attack Pattern
Soul Fysh has a 5-turn attack pattern, which it repeats like most bosses. It consists of debuffs, status effects, and even invulnerability.
Turn 1
Right in the beginning, Soul Fysh puts one Beckon in your discard pile and one in your draw pile. This status card costs 1 Energy, and failure to exhaust it during your turn will do 6 damage.
Since you cannot block this damage, it is advised to remove them rather than try to block when you get these in your hand. It becomes a bigger problem during turns when Soul Fysh is aggressive.
Before it inflicts the Beckons, you can cast whatever damage you can, since there isn’t much else you can do.
Turn 2
In the second turn, Soul Fysh will be aggressive and deal over 15 damage. If you didn’t get any Beckon in your hand, you can block some of this and focus on attacking.
This and the next two turns will be the openings (the latter more so than this) where you can go on the offensive side. Dish out as much damage as you can and make sure you discard any Beckons that you get.
Cards like the Regent’s Reflect are really handy here because your block essentially deals damage, and you can easily discard status cards.
Turn 3
Soul Fysh will deal a weak attack of less than 10 damage and give another status card to the player’s draw pile. Since the incoming damage is low here, you should ignore it and focus on your attacks.
If you had used the previous turn to set up for this one, make it count because tanking hits is only viable in early rotations. You will likely have less HP later on, and risky plays can be costly.
Turn 4
During the fourth turn, Soul Fysh will buff itself with Intangible for one turn. While it has Intangible, all damage that Soul Fysh takes is reduced to 1, completely negating all your heavy hitters.
As such, this will be the best opening to deal whatever damage you can before it casts the buffs. Make sure to leave some blocks in your draw pile because you will use them in the next turn.
If you have any Beckons but believe that 1 Energy would be better spent on the offense, you can tank the hit. If you can’t afford the HP loss, simply discard.
Turn 5
Soul Fysh will remain Intangible during this turn. It will set itself up to debuff you for 3 Vulnerable and deal over 10 damage in its turn.
Since you can’t do a lot of damage, focus on blocking its attack and discard whatever Beckons you may have in your hand.
Second Rotation
Turn 6 will be the beginning of Soul Fysh’s second rotation. It will be slightly different this time because of the 3 Vulnerable inflicted on you.
Unlike the first rotation, tanking hits will not be a viable option anymore. If things worked out well for you earlier, the boss should be much lower in health, making it easier to find an opening to deal the finishing blow.
The strategy for this rotation will be to block incoming damage, discarding Beckons, and finding that opening.
Useful Tips
If you have cards that work well in your setup, like Acrobatics and Burning Pact, use them to discard or exhaust the Beckons in the aggressive turns.
The best you can do during Act 1, where the Soul Fysh awaits, is take low-cost cards to make Energy management a bit easier.
Once you understand the pattern, Soul Fysh is a relatively easy boss to deal with. It only becomes a threat during its second rotation when you are inflicted with Vulnerable.
By that time, however, you should have dealt some serious blows and brought it to its knees… if it has any.
If you are still struggling, you can check out our complete Regent guide or the beginner guide to improve your setups.