In Diablo 4, Strongholds are demon-infested locations throughout the Overworld which players will have to liberate in order to turn them into safe havens. Each stronghold will have a number of objectives players will need to complete, including a boss battle at the end. While bosses will typically have much more health and more powerful attacks than regular enemies, boss battles can vary in difficulty, particularly depending on the player's chosen class and equipment.
Most bosses will have three-to-four different phases of attack in which they must be defeated, with each stage becoming progressively harder as the boss's health lowers. Unlike World Bosses, which are PvE multiplayer World Events, Stronghold bosses can be taken on solo as part of Diablo 4's main campaign.
15 Frosthorn, Ice Clan Champion
Frosthorn, Ice Clan Champion is a large, horned rabbit-like monster located at Malnok in the Fractured Peaks region. Frosthorn wields a large axe that can cause damage from close to medium range, along with frozen projectiles to attack from range. He can also spawn frost pools as an AoE ability which players will need to watch out for.
Fortunately, this creature's attacks are relatively slow and easy to avoid, allowing for additional damage to be inflicted from behind. Following his defeat, players must head to the Wanderer’s Shrine and interact with it in order to liberate Malnok.
14 Captain Ezmin
Captain Ezmin is a rogue-style fast-moving and dagger-wielding boss located at The Onyx Watchtower. Captain Ezmin is a fairly straightforward boss with relatively predictable abilities. Primarily he will use invisibility in order to try to sneak attack with his close-range dagger, but he also has an AoE ability in which rocks will fall from the ceiling.
Ezmin also uses fire bombs and will do so with increasing regularity as the fight progresses. Like many bosses, Ezmin will also summon waves of lesser-powered minions, though they shouldn't pose too much of a threat in this instance.
13 Duz'Agur, Eriman's Bane
Duz'Agur is a Fallen Shaman located at Eriman's Pyre. Primarily relying on magical attacks, Duz'Agur will use a Blood Trail ability along with Fire Breath and a Fireball Attack. All three attacks are relatively easy to read and dodge, though the Fireball can be particularly dangerous from close range.
The shaman will be most vulnerable while casting, so players should ensure that they launch counter-attacks as soon as possible after avoiding his spells. Once defeated, the spirit of Eriman will be freed, allowing players to progress and find the Wandering Shrine.
12 Dianthus
Dianthus is a snake-like demonic boss located Vyeresz in Hawezar. Using poison-based attacks as well as sporting two vicious fangs, Dianthus is able to stun players in addition to causing fair amounts of damage if these attacks land. However, much like the previous Stronghold bosses, his attacks are often telegraphed, allowing players to learn and overcome his battle patterns relatively easily.
Dianthus does also have a projectile ability as well as a blood pool AoE ability which can be quite damaging, but provided that both of these special attacks are avoided, the fight should be relatively straightforward.
11 Baelgemoth, Infernal Tormentor
Baelgemoth is, as his name might suggest, a large ogre-like creature wielding a large flaming mace. He is located in Tur Dulra, in the Scosglen region. In addition to throwing large, arcing swings with his colossal mace, Baelgemoth can also utilize fire breath and possesses several flame attacks.
Despite this, he is still relatively slow-moving, and players should be able to quickly read the pattern of his attacks in order to time dodges to avoid them. Once defeated, heavy rain will fall to extinguish the surrounding flames, and players can head north of the Great Oak in order to find the Wanderer's Shrine.
10 Tidewitch Ne'Gana
Tidewitch Ne'Gana is a slight step up from the previous stronghold bosses and possesses a wider variety of attacks and abilities. Located at Hope's Light in Scosglen, this giant witch uses both smash attacks and spawning ripples of Wretches to attack the player for her.
Despite her large amount of health, Ne'Gana is particularly vulnerable to attacks from behind. The main challenge of this battle lies in fending off the Wretches before becoming overwhelmed, whilst simultaneously dealing as much damage as possible to the boss.
9 Negala, Torvala, And Kozira, Lilith's Chosen
Negala, Lilith's Chosen is a demonic priestess located at Nostrava. Upon commencing battle with her, she will summon two further demons, Torvala and Kozira, and players will have to defeat all three in order to progress. The three demons will primarily utilize homing attacks which follow the player around for a certain distance.
In addition to this, the three demons will also have a Shockwave and Exploding Pools AoE ability, but fortunately, they all possess the same attacks so there is not a huge amount of variation to look out for.
8 Nilcar, Forgotten Bishop
Nilcar, Forgotten Bishop is a vampire boss located at Kor Dragan. This boss will primarily utilize blood attacks such as Blood Pallets and Blood Projectiles which are both ranged abilities. He will also summon additional mini-bosses for players to fight alongside him.
Nilcar also has the ability the revive and regain health, so it is important that players do not become too distracted in battling with the lesser bosses. Once Nilcar is defeated, the Wanderers Shrine for Kor Dragan can be found in the northeast.
7 Dark Cardinal Maldul
Dark Cardinal Maldul is a powerful cultist boss located at the Altar of Ruin. This boss is a caster type relying on spells and summoning in order to produce his attacks. Most of the Cardinal's attacks will first be laid out with occult patterns which appear on the floor. Players must avoid these markings in order to prevent suffering damage.
What makes this battle difficult is the fact that players must first defeat two waves of enemies prior to Dark Cardinal Maldul even spawning. These include The Annihilator and the Unholy Elite. Like most other bosses, the best way to inflict the most damage upon him is to attack from behind.
6 Dame Mariam, Sir Thom, And Sir Morholt, Crusader Champions
Another trio of enemies that together form a singular Stronghold Boss are the Crusader Champions located at Crusader's Monument in the Hawezar region. While the battle will start with players facing off against Sir Thom alone, the other two champions will quickly enter the fray once his health is below a certain threshold.
Dame Mariam is the second to enter, with Sir Morholt being the final boss for players to defeat. Sir Thom will use a projectile attack which should be straightforward for players to dodge. Dame Maryam has a slightly more challenging homing ability, and Sir Morholt will make use of a Wave Attack.
5 Utulku, The Voice Below
Utulku, The Voice Below is located at The Ruins of Qara-Yisu. This shaman-type boss will primarily use Lightning Strike and Lightning Bolt attacks, which will get progressively stronger as his health is gradually lowered.
In addition to the boss himself, there will also be swarms of Cursed Qara-Yisuni for players to fend off, though it should be enough to simply thin their numbers rather than trying to eliminate them all at once. It is best to use a combination of both melee and ranged attacks in order to deal as much damage as possible.
4 Fionnir The Mad Druid
Fionnir, The Mad Druid is a corrupted Druid located at Moordaine Lodge in the Scosglen region. She will primarily use wind-based attacks such as cyclones and wind blasts, but she also has a powerful body slam attack once her form changes below 40% health.
Defeating this boss will require players to learn her various attack patterns, after which they should be able to avoid them and strike counter-attacks. Players must be wary that Fionnir can still use her casting attacks even after she has shape-shifted into bear form.
3 Molqarth The Hungerer
Molqarth The Hungerer is a large barbarian-type boss located at the Temple of Rot. The challenge of this battle lies in the fact that it will take two efforts: one to defeat Molqarth and the other to defeat the Spawn of Molqarth. While Molqarth himself will rely on melee attacks predominantly, he can also utilize Poison Pool and Poison Projectiles for players to be wary of.
The Spawn of Molqarth will also use these toxic abilities, only with faster melee attacks and better maneuverability. Players can tactically reposition themselves to avoid the poison pools and therefore attack the Spawn without suffering poison damage from the environment.
2 Rashta Reborn
Rashta Reborn is a powerful undead boss located at Alcarnus in Kehjistan. Wielding both a huge scythe and an array of dark blood magic abilities, Rashta is one of the harder Stronghold bosses players are likely to encounter throughout Diablo 4.
Rashta will make use of Projectile Ring attacks which will fall down and cause an AoE attack as well as a Soul Attack and Blood Attack which will both need to be avoided. Rashta will also periodically summon Imperfect Simulacra to fight alongside her while shielding herself with blood.
1 High Priestess Hadar
High Priestess Hadar is a formidable caster-type boss located at Omath's Redoubt and is likely the toughest stronghold boss in the game. Using both summoning and teleportation abilities, High Priestess Hadar has an array of powerful magic at her disposal.
Most of her strongest attacks revolve around projectiles and teleporting, which she can perform across varying distances around the Stronghold. Players must try to stay as close as possible while inflicting maximum damage since there will also be an army of Skeleton minions to contend with.
Diablo 4 is available on PC, PlayStation 4, Xbox One, PlayStation 5, and Xbox Series X/S.