How to Defeat the Netherbrain in Baldur’s Gate 3 (BG3)

Defeat the game's last boss with ease if you're well-prepared.

By GamesRecon

If you’ve gone through the whole storyline of Baldur’s Gate 3, you know that it’s been a wild ride full of twists, turns, and some seriously tough battles. But nothing quite compares to the final major showdown you’re preparing for facing the Netherbrain. It’s the grand finale where everything you’ve learned and every ally you’ve gathered comes into play. This creature is not a typical Elder Brain you have known in the game. He is now a formidable foe in the Illithid empire also known as Absolute, he’s got a major power-up from hanging out with the Crown of Karsus for way too long.

Now, I won’t sugarcoat it – taking down the Netherbrain is no walk in the park. This final boss in BG3 is one of the hardest to face, there are some strategies you need to master if you want to stand a chance. But that’s what makes it fun and also think of the bragging rights. Defeating the Netherbrain in Baldur’s Gate 3 means you can wrap up the game and bask in the glory of being the hero who saved the day.

Baldur’s Gate 3: How to Defeat the Netherbrain in BG3

Netherbrain Boss Fight Strategy Guide

This brain has leveled up big time kinda like the usual Illithid mastermind but with extra bells and whistles that make it very tough; so, expect the unexpected. You need to bring your A-game in terms of damage. You need companions who can dish out the hurt, and lots of it – the ones who can swing, zap, or whatever their way through multiple attacks in a turn are your MVPs here. Also, nimble feet are a must – you’ll have to steer clear of the sticky places that are about to give way.

Winning this fight isn’t just about brute force but you’ve got a task: get your party’s Illithid to the Crown of Karsus. This part is crucial – your Illithid buddy needs to use their action to influence the Netherbrain. During the process, you’ll need to clear out the enemies camping on top of the boss first. You must attack, dodge, or fly whatever it takes to get to that crown. Once there, it’s all about activating and channeling a spell to open up a portal. But remember, if your group gets affected by any nasty status like being Stunned or Knocked Out, you will need to start again. Nail it, though, and you’re on to the next stage of the boss battle.

Initial Phase: Reaching the Crown of Karsus

Baldur's Gate 3 Netherbrain Boss Fight

Getting to the Crown of Karsus is a very crucial part of this battle. It’s on the opposite end of the Netherbrain, and getting there is a bit like navigating a maze on a timer. And, of course, you also need to bring your Illithid friends there with you. Whether it’s the Emperor or Orpheus, one of these brainy companions has to be the one to activate the crown.

Not everyone in your squad needs to reach the crown. You need to make sure your Illithid part member stays alive and can get within a hugging distance (about eight meters) of the crown. Once there, they need to focus for two turns to activate this magical, portal-opening spell.

My suggestion and also the best tactic here is to stick together with your companions. Move your squad as one unit, covering as much ground as you can each turn, and don’t forget to throw some punches (or spells, or arrows) during that. Now, when you think you’ve got a handle on things, the Nautilod appears, raining down bombs from above. These explosives are bad news, marking spots that’ll explode soon; the trick is to keep moving and avoid these danger zones.

Remember, while your team members might not be the tackiest, they’re great for distracting foes and chipping away at their health by adding some power to your attacks. And for the finale of this phase: if you’re not up close and personal with an enemy and your magic tricks or dash moves are all spent, you have to keep running towards the crown and reach there in one piece.

Dealing with the Dragon: It’s big, it’s bad, and it breathes fire – typical dragon stuff. While you don’t have to take it down, it’s a good idea if you can. It’s like that one overpowered enemy in a video game that you can skip, but defeating it makes life so much easier. The dragon delivers massive damage, especially with its flame breath and multiple blows at once. To deal with him, Hold Monster and similar spells can halt it dead in motion. If you manage to defeat this beast, you’ll even earn the “Interfectorem Draconis” achievement.

Furthermore, the mind flayers aren’t going to stand around and let you do your thing. They’ll be coming at you, trying to interrupt the process; you need to protect your Illithid at all costs, using your allies, spells, and sheer grit. If you manage to pull it off, and I believe you can, the portal to the Netherbrain’s psyche opens up. Before you step through that portal, gather your party, heal and buff up, and then enter the portal for the final round.

Final Phase: Inside the Netherbrain

The last showdown inside the Netherbrain

You’ve made it through the gauntlet and once you’re inside the Netherbrain, the goal here is pretty straightforward – but not easy. You need to deal a total of 300 points of damage to the Netherbrain in just 5 turns. The Netherbrain in BG3 will not throw punches or cast spells, but don’t let that fool you. It’s a crafty one; it’ll mark areas in the arena that will be destroyed in the next moments. Keep your eyes peeled and your feet moving.

This is where you pull out all the stops, cast your most powerful spells, activate your adrenaline surges and Ki points, and then launch any devastating combos you have. You’ve got to keep an eye on that turn counter because time is not much on your side. You need to average about 60 damage per turn to beat the clock. It sounds like a lot, but with the right strategy, it’s possible. Don’t forget, you can bring your entire party into this fight. The more, the merrier – and in this case, the more damage you can dish out.