Out of all the bosses provided by Cataclysm, the Netherite Monstrosity will be one of the easier ones to defeat, especially compared to the Ignis. The fight hasn’t many complex mechanics, though you will require protection from lava and fire.
Where to find the Netherite Monstrosity
To find the Netherite Monstrosity, you must first encounter a Soul Blacksmith within the Nether. This is a sizeable outdoor-style structure that resembles a Forge. Due to their size and the fact that they spawn in the open, they shouldn’t be too hard to find.
If you are struggling to find a Soul Blacksmith, you can use the command /locate cataclysm:soul_black_smith, or /locate structure cataclysm:soul_black_smith on Minecraft 1.19+. Using these commands will require you to be in cheat mode, which is still possible in a single-player by using the ‘Open to LAN’ option.
Alternatively, the Eye of Monstrous can be crafted from an Eye of Ender, 4 Buckets of Lava, 2 Netherite Scrap, and 2 Blackstone. In the Nether, holding and releasing the Eye will direct it to the nearest Soul Blacksmith.
As soon as you enter the Soul Blacksmith, the Netherite Monstrosity will awaken from its slumber. It rests in the Soul Fire, near the back of the arena. Also within the Soul Blacksmith are blocks that might be useful during the fight or after, such as Anvils and Blast Furnaces.
Defeating the Netherite Monstrosity
Entering the Soul Blacksmith will cause the Netherite Monstrosity to wake up and walk toward you. If you’re at a distance, the Netherite Monstrosity will often launch a projectile at you, which summons pools of lava.
These are easy to deal with, provided you have fire resistance, though they will massively slow your movement. Bringing blocks like Dirt or Netherrack can be placed on the lava source to clear it or to stand on.
If you’re close to the Netherite Monstrosity instead, it will conduct a melee attack. During this, the Monstrosity will slam the ground dealing large amounts of damage and knocking you up. You’ll then take fall damage, so Feather Falling might be helpful here.
Bringing Enchanted Netherite equipment, a Sword/Axe, and an Enchanted Bow and Arrows is recommended. Sometimes, the Monstrosity will resist arrow attacks, but most of the time, they’ll hit. Tank the melee attacks and repeatedly hit the Netherite Monstrosity with the Axe if possible.
Otherwise, there is a much easier option of gaining height and fighting the Netherite Monstrosity from above. Then you’ll be immune to melee attacks, and the Monstrosity will rarely launch lava, and when it does, you’ll be immune.
After defeating the Netherite Monstrosity, two items are dropped. The first is the Monstrous Horn, which can be used to create the Monstrous Helmet, an upgrade to the Netherite Helmet and provides remarkable effects when below half health.
The second item is the Infernal Forge, a weapon in the style of a hammer. Although it can also be used as a Pickaxe, allowing you to mine blocks with it. It has an attack damage value of 13 and an attack speed of 0.8.
When right-clicking with the Hammer equipped, you can deal damage in a small area while sending nearby enemies into the air. This effect has a short cooldown but is very powerful in fights. As a Pickaxe, the Infernal Forge is even able to break through Obsidian, allowing you to collect it.