To capture all 15 strongholds in Diablo 4, you will have to take on the bosses within. One of those is Fionnir, the Mad Druid. Defeating Fionnir in Diablo 4 can be quite a challenge as he is one of the toughest stronghold bosses, even if players are prepared for the fight.
A corrupted druid, Fionnir will remind you a lot of Airidah, Keeper of the Dead from the Diablo IV campaign. Both bosses behave in a somewhat similar manner, constantly spamming wind tornado attacks. Fionnir even transforms into other creatures making this fight quite a challenge.
Diablo 4 Fionnir, the Mad Druid location
As mentioned before, Fionnir is the boss within a stronghold. In order to fight Fionnir, players will have to enter the Moordaine Lodge stronghold in Scosglen. Moordaine Lodge is in the southeast part of Scosglen, North of Shrouded Moors and East of Strand.
Fast travel to the Tirmair waypoint in Scosglen and walk over to the stronghold.
Clear the objectives within and you will eventually have to face Fionnir. Fionnir is present in the Lair of the Beast in Moordaine Lodge, the last area to the Northwest within the stronghold.
How to defeat Fionnir in Diablo 4
Fionnir is a druid who specializes in wind attacks. Her attacks cover a large ground and usually home in on the players’ location. As a Druid, Fionnir also shapeshifts halfway through the fight and introduces new attacks in addition to the previous ones. This can all get a bit overwhelming for the players, but there is absolutely nothing to worry about.
Fight with Fionnir takes place in three phases. She always starts her first phase as Beast of Moordaine, a Werewolf. During this phase, Fionnir uses physical attacks in the form of claw slashes. These attacks are fast and can deal a lot of damage.
Try to dodge and keep your distance. Having a tanky character in Diablo 4 like the Barbarian class or a ranged one like the Sorcerer class helps a lot with the Fionnir fight, especially in the first phase.
Around 80% of total health, Fionnir appears in her true form. She carries a massive staff which she uses to deliver swinging attacks (physical in nature) and cast wind magic. Fionnir’s physical attacks are extremely slow and can be dodged with minimal effort. Her wind attack is telegraphed by a circle on the ground.
Keep your distance as this area soon gets occupied by a cyclone. This cyclone follows the players through the arena but their tracking is poor, to say the least. Just sidestep and keep your distance to avoid any damage. Fionnir summons three cyclones simultaneously in the form of a V in front of her. These cyclones cover a lot of area on the screen but they are still pretty easy to avoid.
Fionnir also summons beasts to aid her in addition to another attack where she throws three wind blasts in a Y pattern around her. This a very fast attack that deals a lot of damage to the players. However, it can be avoided easily by noticing the markings on the floor.
As soon as her health approaches 40%, Fionnir enters into her final form, a Werebear. In this form, Fionnir gets extremely erratic, and her moves-set increases.
Fionnir introduces a new slam attack to her arsenal. The bear attacks the players with an overhead slam using its paws. This is a slow attack that players can judge by the animation, but it is always followed by 6 wind blasts in starburst shape originating from the point of slam attacks impact.
Fionnir in her werebear form uses the same cyclone attacks. However, she summons 5 cyclones in this phase instead of 3.
With a lot of minions, cyclones, wind blasts and a massive Werebear in the arena, the third phase turns the whole fight upside down in favor of Fionnir. The only way to survive this onslaught is to be very agile. Keep moving through the arena while dealing any damage you can to Fionnir. This phase is a real test of endurance and patience.
Fionnir has a lot of health as compared to the other stronghold bosses in Diablo 4. She hits like a mean truck and her magic put the players at a distinct disadvantage. But with properly upgraded stats and defensive skills equipped in addition to our detailed guide, Fionnir can be put out of her misery easily.
Interacting with the Wanderer’s shrine after defeating Fionnir completes the Moordaine Lodge stronghold. This also unlocks Twisted Hollow and Ferals’ Den dungeons.
