Your journey through Baldur’s Gate 3 will bring you up against the deadly Netherbrain, the one who has been pulling all the strings since you first crashed. There’s a lot that can happen here, but your primary focus is to defeat the Netherbrain and save Baldur’s Gate.
There are several strategies you want to consider when facing off against the Netherbrain. The strategy we suggest may not work for you, and you might have to adjust certain things, but it should provide you with an overall idea of how to tackle this fight best. Again, your goal is to defeat the Netherbrain, and there’s a time limit on how long you can take before things get out of control. Here’s what you need to know about how to beat the Netherbrain in Baldur’s Gate 3.
How to beat the Netherbrain in BG3’s final battle
The primary goal of this fight is for the Illithid party member to reach the Crown of Karsus and open a direct connection to the Netherbrain. How you do this is entirely up to you, but don’t waste time fighting the dragon, the other Illithids defending the brain, or The Emperor. Instead, focus entirely on getting to the Netherbrain and surviving. You can see the entrance 40 meters away from where you start to the north.
It should be fine with whatever character is Illithid in your party. It’s only vital that you get them to the Netherbrain, and then you can proceed forward.
If you as an Illithid, or your party-member Illithid, take Stun, Polymorph, or Knock Out damage while influencing the Netherbrain, the process starts over.
Reach the Crown of Karsus
To defeat the Netherbrain, you must reach the Crown of Karsus. Doing so is difficult, as several enemies are atop the Netherbrain, and more will spawn. However, not everyone needs to get the Crown. You only need the Illithid party member to reach it and open a portal to the Netherbrain.
To interact with the crown, you must have your Illithid ally alive: either the Emperor, Orpheus, yourself, or a party member who has transformed. You’ll need to be within eight meters to activate the spell and then channel the spell for one turn.
Thankfully, you have the opportunity to heal just before the brain stem, which you need to interact with to reach the final battle, so make sure you do so.
We took several attempts at this mission before finally completing it. We found the best tactic is to spread out your party members, but each went a different route. It’s a good idea to split up your Baldur’s Gate 3 team to avoid the dragon’s flame attack or being swarmed by multiple enemies. I usually have one of my party’s tanks following the Illithid party member, and the rest go in the opposite direction, all meeting at the middle, toward the crown.
After four turns, a Nautiloid spawns above and drops bombs across the area. However, if you’re quick with your movements and smart about your positioning, reaching the Netherbrain in Baldur’s Gate 3 before getting to this point is entirely possible. The real trick is protecting your Illithid party member from taking damage or something that interrupts their spell.
Reaching the other side of the field can take time and effort. You want to avoid stepping on the brain matter at the center, and instead stick to the outside ring. While this might take longer to reach the Netherbrain in Baldur’s Gate 3, it prevents you from triggering tentacles that spring up from the ground, and they have a chance to grapple your characters, immobilizing them and turning a bad situation into an even worse one.
As you’ve made your way to the other side, there’s a good chance a companion or two might be downed as you attempt to evade the many attacks from this Baldur’s Gate 3 encounter. Although an ally might go down, reviving them is always recommended. Even a single turn of not having a companion attacked is a huge bonus. The more targets your enemies have to deal with, the better, so long as you still prioritize activating the portal at the base of the Crown.
To get close to the Crown of Karsus, utilize abilities that allow you to fly or warp to a location. If you don’t have any with a character and have no enemies to attack, simply using a dash will suffice.
Aside from the Dragon’s powerful AoE attacks, the Mindflayer enemies are your biggest problem, as they can easily stun you with an attack, forcing you to miss a turn. If too many of these stack up, the fight becomes even more complicated. We used allies and summoned companions to focus on the Mindflayers, which usually resulted in them being targeted and not party members. If you didn’t use any of the summons that you could have called on during your ascension to the Netherbrain, using an action in Baldur’s Gate 3 to assist you during this fight is a good idea. Make sure to look through those choices if you need additional help.
After you have activated the spell and channeled it for a turn, a portal will open to take you to the final stand-off against the Netherbrain itself.
Enter the Netherbrain’s Psyche
The Netherbrain has no direct attacks, but is a deadly foe, as it will highlight areas of the arena that will be destroyed on the next turn, and it must be defeated within five turns. You’ll want to try and reach the bottom platforms to confront the brain with your melee fighters, but ranged combatants can hit the Netherbrain at nearly any position. Having a mix of both will be good for this final battle.
You want to be careful when moving allies through the portal and facing off against the Netherbrain. As more allies enter this area, there’s a chance the Netherbrain will destroy specific segments of the platforms. Any Baldur’s Gate 3 character on these platforms falls to their death, and it’s instant. You’ll need to continue moving around the arena and use as many turns as possible to fight the Netherbrain. Hopefully, you didn’t use everything up trying to reach this point.
You do not need all your allies to be in the portal and the fight outside will continue. If the Netherbrain is defeated in time, the allies outside are still safe and feature in the final cutscene.
Any ally with multiple attacks in a single turn is precious in this fight, or someone with an attack capable of doing high damage. At 300 health, the Netherbrain is sturdy, but can be defeated within the timeframe.
Thankfully, no enemies on the Netherbrain attempt to go through the portal. Only you and your party members can make it through. It’s also a good idea to have plenty of Baldur’s Gate 3 saves to reload and attempt this fight again. A lot can happen, but preparation is critical, and having multiple types of weapons is always a good idea.
