A Complete Guide To Playing A Fiend Warlock In 5e D&D

“Go to hell!” spat the guard captain. The Warlock grinned as sparks began popping from her fingertips. As the sparks turned to crackling flames, the guards shied away. “I’ve already visited,” said the Warlock, “and I’ve brought you a souvenir.”

Table of Contents

Immolation is the sincerest form of flattery. Fiend Warlock knows this best, specializing in fire spells that turn battalions of enemies into mass-barbeques. The fire of the Lower Planes runs hot in the blood of Fiend Warlocks, and they are more than happy to share.

For sheer damage output, not many classes can compete with Fiend. Between the base Warlock options and the upgrades the subclass provides, Fiend has almost no offensive weaknesses in combat.

Fiend will appeal to those who tire of bland roleplay and would rather solve arguments by igniting their opponent. If you are ready to sign a literal deal with the devil, read on to find out how to play this devastatingly powerful Warlock subclass.

Using This Guide

Everything in this guide has an emoji, ranking how useful a given ability or feature is to playing this class effectively.

✅ — An absolutely crucial feature. Often forms the backbone of a class’ look and feel. Will provide some bonus that can’t be found through other means.

🆗 — A solid feature that does its job well. Not game-breaking, and certainly replaceable, but a strong choice that shores up some weakness.

⚠️ — A debatable choice. Could work for a specific build, but otherwise is either a wasted opportunity or is just weaker than other alternatives.

⛔ — Outright bad and detrimental. This weighs down the class and just takes up space on the character sheet. A weakness you will have to accommodate for.

These rankings are meant to help you create an optimized class build but remember—DnD isn’t a game where you need to win to have fun. Weaker but flavorful builds also have their place and can make for fulfilling characters.

How To Play A Fiend Warlock

Fiend loves to kill, specifically with fire. The subclass is built to deal damage and kill high-health targets (Striking). You can also use your reputation for murder to help intimidate people during roleplay moments.

Your party will turn to you when an enemy needs to be killed quickly. Focus your build to deal damage in big bursts rather than slowly injuring enemies over time. Ranged damage is where you excel, so be wary about getting into melee range except when absolutely necessary.

Your subclass features improve your defenses somewhat, but some spells need you to get close to enemies, so it’s a wash. Look for extra defensive options in order to stay alive. Teleport and blink effects are great for this, as they whisk you away from danger.

Being An Effective Striker

Look to try and maximize your damage-per-round. This means that whenever possible, your action, bonus action, and reaction should be spent dealing damage before the initiative order gets back around to you. The most basic way to manage this is by concentrating on a spell which allows for recurring damage with a bonus action, then also casting a normal spell and hitting with an opportunity attack.

You have some very strong area-of-effect damage spells, so pick up as many as possible. Let enemies group up, them fry all of them at once to get the most value out of your limited Warlock spell slots. Also stack effects like the Elemental Adept feat and the hex and elemental bane spells to maximize the damage of every spell you cast. 

You won’t be able to cast spells all the time, so eldritch blast and your Invocations are good ways to still be impactful in combat without using up your spell slots.

Fiend Subclass Features

Your subclass features make you into a killing machine, giving you many more offensive options than base Warlock. There are also several features designed to keep you alive during combat, so you can afford to risk getting closer to enemies and crisping them up with close-range fire spells.

✅ Expanded Spell List

1st Level

✅ Burning Hands

Fiend gets a number of solid damage spells with an area-of-effect to hit several targets. Burning hands is the first of these, giving you good damage that scales at higher levels. The range is relatively small though, so you’ll have to risk getting up close to enemies.

⚠️Command

Fine at very low levels, but you’ll get access to the 2nd Level spell suggestion very quickly, which is a strictly better version of command.

2nd Level

🆗 Blindness/Deafness

Not bad for weakening enemies by blinding them and making their attacks miss more, especially when cast with a higher level spell slot so you target a whole crowd.

✅ Scorching Ray

This gets outclassed by eldritch blast at higher levels, but pummeling an opponent with nasty fire rays is a great ranged option. This spell scales with higher level spell slots too, and another fire damage spell can’t hurt if you have abilities that reward you for sticking to one damage type.

3rd Level

✅ Fireball

Ah, the infamous fireball. Nothing beats this for raw efficiency, particularly when you hit multiple targets, which you can manage quite often. This will become your go-to damage spell.

🆗 Stinking Cloud

A strong control spell that can make enemies skip turns, a very powerful effect. Heavily obscuring the area can also limit line-of-sight for attacks.

4th Level

🆗 Fire Shield

Very similar to armor of agathys, but less powerful. The only real reason to use fire shield instead is that your Dark One’s Blessing feature can step on armor of agathys’ toes with the temporary hit points, so fire shield is an acceptable alternative.

✅ Wall of Fire

Stupid good at preventing enemies from maneuvering while also burning them to ash. Offers lots of value over several turns in exchange for your spell slot.

5th Level

⚠️Flame Strike

Not as wide an area-of-effect as fireball, which also deals more damage when cast with a 5th Level spell slot. Only useful if you need to deal radiant damage.

🆗 Hallow

Not the kind of effect Fiend specializes in, but powerful nonetheless. Combining the energy vulnerability option (choosing fire, of course) with your suite of fire spells can really put the hurt on a crowd of enemies. The slow casting time is the biggest downside here.

✅ Dark One’s Blessing

It’s hard to calculate just how much damage this will soak up over the course of a campaign, but it will be a lot. If you can reliably pick off small enemies (which is what eldritch blast and the Fiend subclass both excel at), you’ll be able to tank attacks as well as most combat classes. Just be aware you can only have temporary hit points from one source at a time, so this won’t stack with, say, heroes’ feast and can even negate armor of agathys. Watch this video from Nerd Immersion for a detailed breakdown of how temporary hit points work in niche situations like these.

✅ Dark One’s Own Luck

A d10 bonus is big. Being able to apply it to any non-attack roll is even bigger. This won’t help you land a hit, but it will help you avoid one. And recharging on a short rest is perfect since that’s when you get your spell slots back anyways.

✅ Fiendish Resilience

One damage resistance wouldn’t be incredible on its own, but being able to swap between resistances is. Knowing you can always take half damage from whatever the monster-of-the-day is hitting you with greatly improves Fiend’s survivability.

✅ Hurl Through Hell

10d10 is a lot of damage, and it’s psychic damage, which is almost never resisted. In addition, you get to remove an enemy from the battlefield for a turn. Even if the damage isn’t enough, one turn without the biggest monster on the enemy team can buy your party time to swing the fight in your favor.

Read our full guide on Warlock spells.

The Perfect Fiend Build

Your subclass spells are your best damage dealing options, so scour the general Warlock spell list for options that improve your defense and maneuverability. Focus on getting hit less with high AC and teleport spells. You also have the most area-of-effect damage of any Warlock subclass, so take advantage of that. Finally, you can pick up some other tools to round out your build with utility or flavor.

Ability Scores

⛔ Strength

Dump stat.

🆗 Dexterity

You can focus on cranking up your AC with a high Dexterity score thanks to a few subclass abilities which give you temporary HP and make it harder to hit you. This means having relatively low health is okay, so use Dexterity as your main defensive ability.

⚠️ Constitution

Fiend is less reliant on concentration spells than other Warlock subclasses, and since playing a low-health character is viable with this subclass, Constitution isn’t crucial.

⛔ Intelligence

Dump stat.

⛔ Wisdom

Dump stat.

✅ Charisma

You want a high spell attack bonus and a high spell save DC so that your spells hit often and do maximum damage. Charisma boosts both up, so prioritize increasing Charisma wherever possible.

Races

✅ The teleport ability that Eladrin gets can help you blink away from danger, as can the fly speed of a Winged Tiefling. Standard and Levistus Tieflings are also good options to sling some hellfire.

Half-Elf, Satyr, Verdan, Warforged, and Yuan-Ti Pureblood are all other great options.

🆗 Aasimar, Changeling, Simic Hybrid, Tabaxi, Triton, and Variant Human make for good Fiend Warlocks, diversifying your skillset a bit at the cost of less focus on your core combat abilities.

Feats

🆗 Elemental Adept

Most of your spells deal fire damage, so fire resistance really slows you down. Getting to ignore those resistances and also dealing more damage on average helps you keep your murderous momentum in a fight.

🆗 Flames of Phlegethos (Tiefing Only)

The off-kilter version of Elemental Adept exclusive to Tieflings. You don’t get to ignore fire resistances, but you do get a Charisma bonus and the ability to burn enemies that come after you with melee attacks.

✅ War Caster

Fiend uses less concentration spells than other Warlock subclasses, but you still have very few spell slots, so maintaining concentration avoids wasted slots. And using your reaction to shoot out another eldritch blast only increases your damage-per-round.

Invocations

✅ Agonizing Blast

More damage on your most-used spell. This also makes picking off weak enemies much easier, so you trigger your Dark One’s Blessing feature more often for nigh-infinite health. Take this Invocation as soon as possible and start racking up kills.

✅ Maddening Hex

You should be slapping hex on anything that moves, so extra damage that helps break up crowds of enemies is a direct upgrade and helps put your bonus action to good use.

Read our full guide on Warlock invocations.

Warlock Pact Boons

As Fiend, your best option is Pact of the Talisman. You’ll be closer to combat than other Warlock subclasses, but you don’t have the combat prowess of Hexblade (you can see just how combat-capable Hexblade Warlock is by checking out our guide to the subclass here). Your talisman greatly improves your survivability and can also help you pass ability checks.

Key to this strategy is the Protection of the Talisman Invocation, which lets you add bonuses to saving throws. Suddenly enemy spells are hitting you a lot less. You might even consider the Bond of the Talisman Invocation to teleport away from danger if things are looking dicey. Pact of the Talisman benefits from spending a lot of Invocations upgrading it, so you might need to deprioritize other spell-granting Invocations to make the most of your Pact Boon.

If your spell list is saturated with combat spells, Pact of the Tome is another decent option, allowing you to pick up additional offensive cantrips, or balancing your list with some utility cantrips and rituals. Pact of the Chain and Pact of the Blade aren’t particularly good for you, since you want to focus on dealing damage through spells.

Spells

Cantrips

✅ Eldritch Blast

The best damage cantrip in the game. Most of your damage will come from this spell. And it uses force damage, which almost nothing resists, so you can rest assured this cantrip will hit hard.

🆗 Toll the Dead

A good offensive alternative if your enemies have high enough AC to block your eldritch blasts. Particularly effective against mooks without the brain power to pass the save.

1st Level

🆗 Armor of Agathys

Fiend is possibly the one Warlock subclass where this spell is not a must-have. Dark One’s Blessing also gives you temporary hit points, and you need the points from armor of agathys in order to hurt enemies with it. You have to choose one or the other, and while this spell is stil excellent at higher levels, its strength is being able to cast it and forget about it. To read more about it, check out this guide from Nerdbear on how to use armor of agathys most effectively.

🆗 Hellish Rebuke

Pretty good damage, scales well at higher levels, and increases your damage-per-round by using your reaction.

✅ Hex

Synergizes so very well with your damage spells to annihilate the target of your ire. You also get to reuse the spell when you make the kill, so it’s very efficient. Once you start stacking this with other abilities that give you bonus damage, you’ll start one-shotting enemies.

2nd Level

🆗 Mirror Image

A stupidly good defensive option that doesn’t require concentration. Let your duplicates soak up a few hits while you focus on taking out enemies.

✅ Misty Step

Maneuverability is important for any subclass that wants to enter the fight. Especially for your spells like burning hands with short range, being in the right place at the right time is key to dealing damage without getting killed.

🆗 Shatter

A decent area-of-effect spell with damage that scales when cast at higher levels. You’ll probably want to use fireball more, but this is a good backup.

3rd Level

🆗 Hunger of Hadar

A very good control spell that slows enemies and makes them clump up, allowing you to pick them off next turn with a blast of fire.

🆗 Thunder Step

More maneuverability, with the added bonuses of taking a friend with you and leaving some damage behind.

4th Level

✅ Blight

This is a lot of damage at range. If there’s a big monster causing problems on the battlefield, dropping it in one turn with this spell can turn the tide of combat.

✅ Elemental Bane

Slap an extra 2d6 damage onto any fire spell you cast, which most of your damaging spells are. Shame you can’t pick force damage for eldritch blast synergy, but this still works to chew through the health of a troublesomely resilient enemy.

🆗 Shadow of Moil

Great defense that makes ranged attacks against you hit less and punishes enemies for getting into melee range.

5th Level

✅ Far Step

Reusable teleportation to always reposition yourself before taking your turn. The strategic advantage cannot be overstated.

✅ Synaptic Static

Simply a lot of damage in a good sized area-of-effect. Many enemies don’t have a good Intelligence save, so this should deal full damage most of the time.

6th Level

✅ Circle of Death

Just an insane size. A 60-foot-radius sphere easily covers most battlefields on its own. And the damage is solid too.

🆗 Tasha’s Otherworldly Guise

Pop this for the defensive bonuses, like two damage resistances and +2 AC. The fly speed is also great, but you won’t use the melee attack effects.

7th Level

✅ Crown of Stars

No concentration, hard-hitting recurring damage, long range attacks, and a good use of your bonus action which often sits unused. This is the culmination of Fiend’s role in life: hurt things well.

8th Level

🆗 Abi-Dalzim’s Horrid Wilting

A large area-of-effect pairs well with some brutal damage. The only reason this isn’t rated higher is that by this point you already have a few tricks in your toolbag that do similar effects.

✅ Maddening Darkness

This is one of the best area-of-effect spells in the game. It covers a massive area, deals a lot of psychic damage (which is the least-resisted damage type), and stays in place to block line-of-sight and deal more damage every turn.

9th Level

✅ Foresight

You get so many benefits from this that you should cast it whenever possible. Once a day, you turn yourself or a friend into a dice god that almost never fails a roll or gets hurt.

✅ Psychic Scream

Only the sturdiest of monsters will survive this spell. Getting to single-out targets is also very nice, instead of relying on them being near enough that an area-of-effect will hit them all.

Equipment

Grab the best armor you can, so that when you antagonize enemies with a burst of fire, you can live to tell the tale. Studded leather is your top pick.

You’ll mostly be dealing damage with spells, but if you are feeling stabby, greatclubs, handaxes, javelins, maces, quarterstaffs, and spears are your highest-damage melee weapons, and a light crossbow is the strongest simple ranged weapon available.

To lean into your fiery personality, you might like to pick up some alchemist’s fire, which is a way to toast enemies without needing to spend a spell slot.


Fiend Warlock is uniquely damaged focused, getting on par with Wizard and Sorcerer for spell damage. If this guide helped you understand how to play Fiend, share it with a friend! And please leave a comment with your favorite fire pun. I’d genuinely love to read through them.

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