Aasimar Fiend Patron Warlock Build Guide

Levels 1-4

Start with your optimal stat block: STR 8, DEX 14, CON 13, INT 12, WIS 10, CHA 15. At level 1, take Eldritch Blast and Hex. At level 2, grab the Agonizing Blast and Repelling Blast invocations to establish your baseline DPR. At level 3, your subclass really comes online. You gain Dark One's Blessing, feeding you temporary hit points whenever you score a kill, plus access to 2nd-level spells like Scorching Ray. This is also when your Aasimar Celestial Revelation becomes available, granting you critical flight. At level 4, take the Fey Touched feat to bump your Charisma to 16 and grab Silvery Barbs.

Levels 5-10

Level 5 is massive: you get 3rd-level spell slots and the Fiend's hallmark spell, Fireball. Drop it on clustered enemies to instantly trigger Dark One's Blessing. At level 6, Dark One's Own Luck comes online; save this exclusively for crucial concentration checks or nasty Wisdom saves. At level 8, take an ASI for +2 Charisma (bringing you to 18). Level 9 brings 5th-level spell slots, allowing you to cast max-power Wall of Fire or the newly acquired Fiend spells Flame Strike and Hallow. At level 10, Fiendish Resilience allows you to choose a damage resistance every short rest. Since your Aasimar traits already cover Radiant and Necrotic, pick Fire or Poison depending on the dungeon.

Levels 11-16

Level 11 grants your third Pact Magic slot and your 6th-level Mystic Arcanum (take Mass Suggestion). Level 13 unlocks your 7th-level Mystic Arcanum; take Forcecage to instantly win encounters without a saving throw. At level 14, you gain the phenomenal Hurl Through Hell. When you hit with Eldritch Blast, you can banish a target and deal 10d10 psychic damage with absolutely no saving throw. Use this to remove the biggest threat from the board for a full round. At level 16, take an ASI to cap your Charisma at 20.

Levels 17-20

Level 17 brings your 9th-level Mystic Arcanum. Take Foresight for 8 hours of advantage on everything and disadvantage on attacks against you. Level 17 also marks your final Eldritch Blast beam, maximizing your at-will damage. For your final ASI at level 19, take Resilient (Constitution) to round out your odd CON score to 14 and secure proficiency in concentration checks. By level 20, your Eldritch Master capstone lets you desperately recover your 5th-level slots in a pinch.

Cantrips

Eldritch Blast is mandatory; it is your primary damage source. Mind Sliver is an excellent secondary cantrip to penalize an enemy's saving throw before an ally drops a control spell. Minor Illusion provides utility and instant cover.

Level 1-2 Spells

Take Command from your Fiend spell list; upcasting it affects multiple targets and scales beautifully. Scorching Ray is great early-game single-target burst, though it falls off later. Avoid Armor of Agathys on this specific build, as its temporary hit points will be constantly overwritten by Dark One's Blessing.

Level 3-5 Spells

Fireball is the reason you chose the Fiend Patron. Wall of Fire is exceptional for battlefield control; combine it with Repelling Blast to push enemies back into the flames. Synaptic Static is a fantastic non-concentration AoE that targets Intelligence and debuffs enemy attack rolls.

High-Level Spells

For your Mystic Arcanum, take Mass Suggestion (6th level) to end encounters before they begin. Forcecage (7th level) is the best spell in the game for isolating bosses. Feeblemind (8th level) shuts down enemy spellcasters. Foresight (9th level) makes you nearly untouchable while guaranteeing your Eldritch Blasts hit.

Fey Touched

Take this at level 4. With a starting Charisma of 15, this rounds you up to 16. It provides Misty Step, freeing up a precious Warlock spell slot, and lets you grab Silvery Barbs or Gift of Alacrity to drastically improve your survivability or initiative.

Resilient (Constitution)

Take this at level 12 or 16. You start with 13 Constitution, so this bumps you to 14, giving you more HP. More importantly, it adds your proficiency bonus to Constitution saving throws, ensuring you don't drop concentration on critical spells like Wall of Fire or Hex when you take damage.

Alert

A phenomenal choice for a Blaster Warlock. Winning initiative means you can drop a Fireball on the enemy formation before they have a chance to spread out or close into melee with your frontline. +5 to initiative makes a massive difference for your action economy.

Tier 1 (Levels 1-4)

Secure Studded Leather Armor immediately to capitalize on your 14 Dexterity. Seek out a Bloodwell Vial +1 to boost your spell attack rolls and save DC, and to recover 5 sorcery points if you multiclassed, though as a pure Warlock, the DC bump is what you care about.

Tier 2 (Levels 5-10)

Upgrade to a Rod of the Pact Keeper +2. This is strictly better than a generic wand because it allows you to regain one Warlock spell slot as an action once per long rest, alleviating the class's biggest weakness. A Cloak of Displacement pairs beautifully with your flight to make you incredibly hard to hit.

Tier 3 (Levels 11-16)

Hunt down Illusionist's Bracers. If your DM allows them, they let you cast Eldritch Blast as a bonus action every single turn, literally doubling your DPR. If those are banned, seek a Staff of Power for the massive AC boost and extra spellcasting flexibility.

Tier 4 (Levels 17-20)

You want the Robe of the Archmagi. It sets your base AC to 15 (17 with Dex), gives you advantage on saving throws against spells, and further increases your spell save DC and spell attack bonus. Combine this with a Rod of the Pact Keeper +3 for absurdly high saving throw DCs.

As a Fiend Warlock, your primary role is the Blaster. You provide burst damage via Fireball and sustained single-target damage via Eldritch Blast. Because your spell slots are severely limited, you rely heavily on your party to handle utility casting, healing, and frontline defense.

You pair perfectly with an Oath of the Watchers Paladin. Their Aura of Sentinel boosts your initiative, letting you drop your AoE spells early, while their Aura of Protection shores up your abysmal Wisdom saving throws. An Ancestral Guardian Barbarian is also fantastic; they lock down major threats, giving you the space to fly via Aasimar's Celestial Revelation and rain down fire unbothered.

Finally, a dedicated control caster like a Clockwork Soul Sorcerer or Divination Wizard makes your life easy. If they drop a Web or Hypnotic Pattern, you can meticulously pick off targets with Eldritch Blast, triggering Dark One's Blessing on each kill without wasting your precious spell slots.

Sorcerer 3 (Divine Soul)

A three-level dip into Divine Soul Sorcerer gives you the Shield and Absorb Elements spells—crucial defensive tools you lack. More importantly, it grants Metamagic. Quickened Spell lets you cast a massive Fireball as a bonus action and still fire an Eldritch Blast with your action on the same turn.

Fighter 2

Taking two levels of Fighter provides Defense fighting style, armor/shield proficiencies (if taken at level 1), and the holy grail: Action Surge. Action Surging to cast two 5th-level Fireballs in a single turn will obliterate almost any mid-tier encounter before the enemy even acts.

• Over-relying on Armor of Agathys: It's a great Warlock spell, but its THP does not stack with the THP from Dark One's Blessing. If you are killing minions consistently, casting AoA is a wasted spell slot.
• Forgetting to rotate Fiendish Resilience: At level 10, you can pick a damage resistance every short rest. Don't leave it on Fire damage when heading into an undead crypt. Always scout and adapt.
• Wasting Hurl Through Hell on doomed targets: Hurl Through Hell happens on a hit. Don't use it on a minion with 10 HP. Save it for the boss to deal 10d10 unavoidable psychic damage and remove them from the board for a full round.
• Ignoring Aasimar Healing Hands: You are a blaster, but you have a free touch heal. Use it to pick up the downed Cleric so they can cast Mass Healing Word. Don't let this feature sit unused.