The Harbinger is a mechanical boss in the Cataclysm mod. It is one of three bosses that spawn in the Overworld, specifically within the Ancient Factory structure.
Finding the Ancient Factory
The Harbinger spawns within the Ancient Factory. This structure is located in the Overworld and is a dungeon that is found deep underground. So get your best Pickaxe, as you will need to do some mining.
The easiest way to locate the Ancient Factory (and the Harbinger) is to create an Eye of Mech, which requires 4 Redstone Blocks, 4 Iron Ingots, and an Eye of Ender. These are very similar to a standard Eye of Ender.
When holding the Eye of Mech, you can use the right mouse button to release it. It will then float in the direction of the nearest Ancient Factory, so keep doing this multiple times. When the Eye of Mech floats above you, that’s when you should start to dig downwards.
Alternatively, some commands can be entered, provided you have cheats enabled. You can use the commands /locate cataclysm:ancient_factory or /locate structure cataclysm:ancient_factory on Minecraft 1.19+.
Within the Ancient Factory, you can find some blocks that might be helpful before going into the fight, such as Anvils, Blast Furnaces, and Grindstones. Then, you will see the large arena containing the Harbinger.
Fighting the Harbinger
It’s safe to enter the area where the Harbinger resides, as it will be shut down. To awaken the Harbinger, you will need to hold a Nether Star and use it on the Harbinger; then, it will wake up, and the fight will begin.
Firstly, the Harbinger has 390 health and 12 armor. When it fights, it switches between missile, rocket, and laser modes. These are easy to counter, provided you have a Shield and some Fire Resistance, as these attacks will set you on fire.
These attacks may also hit you with the ‘Wither’ effect, so bring plenty of food. If you think it could be helpful, bring buckets of milk to remove any negative debuffs. Every so often, the Harbinger will use a new (and powerful) ability, the Death Laser.
After powering up for a few seconds, the Harbinger will release a powerful laser onto enemies, dealing lots of damage. When this attack happens, the best thing you can do is simply run away and keep healing. Sometimes, the Harbinger will do a charge attack, which can destroy blocks within the arena.
Though it’s also possible to use the Death Laser to your advantage, EMP blocks are placed around the room, which can be charged up if the Harbinger hits them with the Death Laser. When these are activated with Redstone, such as the Lever placed alongside them, they will release an EMP pulse.
If the EMP pulse hits the Harbinger, it will be disabled for a few seconds, allowing you to either deal damage or heal yourself. Other than that, the fight shouldn’t be too difficult and might only take a minute or two.
There are two phases to the fight with the Harbinger. Once it reaches half health, the Harbinger will become shielded, making it immune to the Bow and Arrow and also giving it health regeneration.
Make sure to bring Enchanted Netherite equipment or better. A good weapon choice would be an Axe or the Infernal Forge, which can be obtained from the Netherite Monstrosity. Because the Harbinger tends to stay in the air, a Bow and Arrow would also be a good idea.
Harbinger Loot
After defeating the Harbinger, players will be given a single Witherite Block. These have no use but can be placed in a crafting window to turn them into nine Witherite Ingots, which are much more helpful.
Using Witherite Ingots, three different weapons can be created, the first of which is the Meat Shredder. This weapon is similar to what the Prowler uses and allows you to deal consistent damage to enemies within a melee distance.
In previous versions of Cataclysm, the Harbinger would drop the Wither Assault Shoulder Weapon. However, this item now needs to be manually crafted. When used, it fires missiles at a target, hitting them with the Wither effect. If the player sneaks instead, it becomes a Howitzer, leaving a dangerous area where it lands and dealing damage over time.
The final weapon that can be crafted is the Gatling Gun, which can be used to decimate enemies’ health quickly. Gatling Guns act as fully automatic rifles and can even set blocks on fire that the bullets touch. You can fire a lot of shots before they need to be reloaded, which will cost 1 Redstone Dust.
Witherite is also required to craft the Mechanical Fusion Anvil. This block allows players to combine items from the Cataclysm mod, which will empower their abilities.
