Lumacchio, who is also known as the “Leader of the Bastards,” is one of the final story bosses in Lies of P Overture DLC. He is found in the Archon Fleet Shipwrecks. Lumacchio’s fight is a challenging two-phase battle that requires preparation and some skills as well.
That being said, this boss does have some interesting weaknesses, like leaving a lot of openings for backstabs or quick attacks, for you to exploit, which we have detailedo ut in this Lumacchio boss fight guide.
Lumacchio Boss Fight Preparation

Fast and close-range weapons like the Salamander Dagger and Acidic Crystal Spear work really well here, allowing you to land quick combos and backstabs. These weapons will shine during those small windows when Lumacchio leaves himself open and gives you a chance to strike.
If you are looking to build Stagger, especially in the 2nd phase, heavy-hitting weapons like the Live Puppet’s Axe or Legion Arms like Flamberge and Cataclysm are also a great choice. Also, remember to carry Purification Ampules to counteract status effects in phase two.
Lumacchio Boss Fight: Phase One

During the first phase of this boss fight, Lumacchio mainly focuses on doing melee combos. His attacks leave short gaps where you can get in a quick hit or perform backstabs.
His attacks also have long enough pauses where you can roll behind him and counter. Also, his red-charged attack is parryable, which creates another great opportunity for a backstab or combo.
During battle, if Lumacchio raises his umbrella, it usually means that he is about to perform either a defensive or a transition move. You can sidestep this animation and deal damage to him from behind. Strike after his recovery animations using a Legion Arm like Cataclysm to deal heavy damage and possibly stagger him.
When Lumacchio’s health flashes white, he may prepare a follow-up move. In such cases, it’s best to create distance and use a Shot Put to disrupt him while staying safe.
Also read: All Legion Arm Locations & Upgrade Details In Lies Of P Overture
Lumacchio Boss Fight: Phase Two

Once his health drops to about 50%, the arena is covered in thick fog, and Lumacchio enters a more aggressive second phase. His attacks become faster and harder to predict, and he starts inflicting Decay status on you.
Fire-based weapons become highly effective in this stage. Tools like the Salamander Dagger or Flamberge are ideal for inflicting burn damage, allowing you to chip away at his health steadily. Keep using Purification Ampules to remove decay and avoid unnecessary damage buildup.
Continue applying pressure through backstabs when possible, and keep using Puppet String or Aegis depending on whether you need space or protection.
Defeating him rewards you with the Golden Snail’s Mask and Tailcoat. After you’ve defeated Lumacchio, you’re given an important choice to make: whether to punish him or leave him.
Also read: Lies Of P Overture DLC: All 10 Weapons Location & Stats
Punish or Leave Lumacchio in Lies of P Overture

Once Lumacchio is defeated, he pleads for his life, giving you the option to either punish him or spare him. Here are the consequences of both choices.
Punish Lumacchio
Choosing to punish Lumacchio results in his death. He gives a short monologue before fading away. After this, a message will appear on your screen saying, “You feel warmer,” and the nearby Stargazer will become available.
Leave Lumacchio
If you decide to leave Lumacchio alive, the scene ends with the same “You feel warmer” message and access to the Stargazer. However, if you rest at the Stargazer and return to his location, you will find a letter from Lumacchio.
In the note, he mocks you and questions your morals, hinting that your mercy may have made you no better than him.
Should You Punish or Leave Lumacchio in Lies of P Overture?

Ultimately, the decision is entirely up to you, and it is safe to say that it does not have any impact on the game’s narrative. Whether you choose to punish him or leave, the story will play out as intended.
That being said, leaving him offers a small extra detail in the form of a letter that adds to Lumacchio’s character and the game’s atmosphere. If you wish to play it out and experience it yourself, then it is recommended that you leave Lumacchio.