Hiring mercenaries is one of coolest new features in Diablo 4's Vessel of Hatred expansion, letting you recruit a famed fighter you can bring into battle with you. These warriors have their own ability tree, granting passive effects, and specialising in either buffing certain stats or applying debuffs to enemies. All in all, they make a big impact in combat.

There are four mercs to recruit in Vessel of Hatred, each of which has a specific fighting style, but if you can't decide on one, you can also bring a second as a reinforcement you call upon for one-off hit and run attacks. Here I'll list my personal pick for the best merc, how to unlock them, plus how they work. I've also included a list of all mercs plus their specialisms and unlock conditions down below.

Who’s the best mercenary in Diablo 4?

The best mercenary in Vessel of Hatred is Raheir in my opinion, which is great considering he's the first one you unlock. Your choice of merc will likely depend on your build, but Raheir has great overall utility no matter your build due to his ability to taunt enemies and grant you damage reduction plus increased armour. His Provoke iconic skill, in-particular, is great for survivability, giving you up to 20% damage reduction based on how many enemies it taunts.

How to unlock mercenaries

You can unlock the mercenaries feature directly through the Vessel of Hatred main campaign. After you arrive in Nahantu, Raheir will show you to The Den; a special hidey hole where his old mercenary outfit, The Pale Hand, used to gather. Once this is unlocked you'll recruit Raheir as your first merc and be able to undertake quests from The Den to meet the remaining three; Subo, Aldkin, and Varyana. 

While you can only have one primary merc, you can also bring a Reinforcement who will jump out and perform one-off attacks when called upon. As you travel with your chosen mercs and defeat enemies, you'll gain Rapport, granting you skill points to level them up plus the Pale Marks currency, which you can also earn by completing open world events. Once the campaign is finished, you can barter these with Fayira in The Den in exchange for aspects, crafting materials, and gear, making them pretty valuable.

Subo

Choose if you want:

• A ranged support specialist who uses traps
• Increased DoT and crit damage to enemies, movement speed, lucky hit chance, or crowd control

This mercenary archer is fairly straightforward to unlock. You can start his A Feather On the Scale quest by reading the Muddy Letter in The Den after you unlock it in the campaign. This sees you venture to the toxic fens in Hawezar, where you help Subo deal with some cultists kidnapping innocents. Subo is effectively a rogue, i.e he's an archer who hits enemies from range and can use traps to apply crowd control debuffs. He can also give you bonus DoT, critical strike damage, or lucky hit chance against enemies hit by his abilities, depending on which skill path you choose.

Aldkin

Choose if you want: 

• A shadow or fire DoT mercenary
• Increased critical strike chance or DoT damage
• Good synergy with shadow-based keywords like daze

Aldkin is a cursed demon child with two different forms, which is indicated by his skill tree specialising in either shadow or fire. His fire skill tree grants increased critical strike chance and DoT damage against enemies hit by certain abilities, while his shadow form offers good synergy with shadow-based keywords like daze, stun, and lucky hit, making him a good partner for a shadow Necromancer say. Acquire the A Nameless Mystery quest by picking up the Archive of Kuo Chosah in The Den and then follow his trail and fight some demons to recruit him.

Raheir

Choose if you want: 

• A taunt-based defensive mercenary
• Damage reduction, increased armour, and elemental resistances

As mentioned above, Raheir is a great all-round merc, granting you ever-valuable damage reduction, extra armour, or a buff to elemental resistances. Raheir doesn't deal all that much damage when he bashes enemies with his shield, but he will taunt them, giving you much-needed breathing space. The best part is that he's the easiest to recruit as well. While the others require you to do separate sidequests, you meet Raheir during the campaign, meaning he's perfect if you want to keep pushing on with the story and not get sidetracked immediately.

Varyana

Choose if you want: 

• An axe-wielding berserker
• Increased attack-speed, lucky hit chance, and bleed-based healing
• Good synergy with Barbarians

Varyana is a cannibal berserker, and as such, she's got great synergy with the barbarian class, providing attack speed buffs, lucky hit chance, and healing based on damaging bleeding enemies. You can start her Slayer's Retribution quest by picking up the Brutal Note in The Den once you unlock it in the campaign. You'll have to complete the Temple of Rot stronghold, free Varyana, and then help her reap vengeance on the cannibal warlords Grelkar and Zolmog.