Delayed Blast Fireball — Complete D&D 5e Spell Guide

Table of Contents

• •Quick Answer
• •Overview
• •Stat Block
• •When NOT to Use
• •Comparisons
• •Spell Slot Efficiency
• •Pro Tips
• •Common Mistakes
• •Usage Tips
• •Synergies
• •FAQ

Overview

Listen, if you're a wizard or sorcerer hitting 7th-level slots, Delayed Blast Fireball is one of those spells that sounds amazing on paper—a bead that ramps up from 12d6 to potentially 18d6 fire damage over a minute of concentration—but in practice, it's Situational at best. It's a trap-setter's dream for ambushes or when you know enemies will cluster up later, outdamaging an upcast Fireball (12d6 at 7th) if you get 6+ turns of ramp-up. But that concentration requirement is a killer in prolonged fights where you'd rather maintain Bigby's Hand or Wall of Force, and most combats end before it hits peak value. Veterans love it for creative plays like parking it in a doorway or synergizing with illusions, but new casters misplay it by detonating early or forgetting enemies can punt the bead. Overall, prepare it if your campaign has downtime ambushes or you're building a contingency blaster; otherwise, slot in Teleport or Forcecage.

Stat Block

When NOT to Use This

• •Fire resistance/immunity dominates encounter (e.g., efreeti lairs).
• •Party needs your concentration for flight, invis, or summons mid-fight.
• •Combatants highly mobile or can teleport away from bead.
• •Underwater/dispersed environments negating AoE.
• •Single-target boss without adds to justify ramp-up.

Spell Slot Efficiency

When worth the slot: Planned ambushes, lair traps, or fights lasting 1+ min where fire works.

When NOT worth the slot: Reactive combats, fire-resistant foes, or when conc needed for flight/mobility.

Pro Tips (Veteran Secrets)

Tip #1: Use a familiar to deliver the bead precisely into hidden spots enemies must pass, like 5 ft behind a door.

Why veterans know this: Familiars have 100 ft range, ignore difficult terrain; turns it into a 18d6 minefield RAW.

This avoids the mistake of: Players forget familiar touch triggers DEX save, wasting the spell.

Tip #2: Combine with Tiny Hut for safe ramp-up during long rests—detonate on attackers breaching.

Why veterans know this: Leomund's works with concentration outside, but bead persists; averages 15d6 on dawn raids.

This avoids the mistake of: Assuming camp attacks are short; this preps for sieges.

Tip #3: Against flying foes, place bead mid-air at their hover altitude for collision detonations.

Why veterans know this: Bead stationary, fliers path into it; beats ground-targeted AoEs.

This avoids the mistake of: Defaulting to ground placement.

Tip #4: Track exact damage: Turn 0:12d6, +1d6/end turn, so minute=18d6 (avg63).

Why veterans know this: Maths outdamage 9th Fireball (14d6=49); sell to DM/party.

This avoids the mistake of: Vague 'big boom' estimates.

Common Mistakes to Avoid

Detonating after 1-2 turns for 13-14d6.

Why it's bad: Wastes 7th slot vs Fireball upcast (12d6 no conc); opportunity cost huge.

Do this instead: Commit to 4+ turns or don't cast; use for traps only.

Placing bead in line of sight without stealth.

Why it's bad: Enemies Counterspell, Dispel, or avoid; visible yellow glow screams danger.

Do this instead: Invisible cast, obscure with fog/clouds, or familiar delivery.

Forgetting touch interaction lets smart foes throw it away safely.

Why it's bad: Rogue succeeds DEX, punts 40 ft into your party for backfire.

Do this instead: Position 60+ ft away, constrain movement first.

Upcasting without plan for extra dice.

Why it's bad: 9th slot 20d6 max still conc-bound; better Meteor Swarm.

Do this instead: Only upcast for 1-off superbombs with Contingency.

Usage Tips

• •Place the bead in chokepoints like doorways or behind illusions for enemies to blunder into, maximizing touch detonations without wasting your turns.
• •Track turns precisely: after 3 turns it's 15d6 (avg 52.5 damage), beating most 7th-level options, but communicate with party to avoid friendly fire.
• •Use in exploration phases for 'booby traps'—cast before resting, detonate on surprise rounds; pairs perfectly with Alarm or guards.
• •Against mobile foes, position high up or in webs/restraints so they can't easily throw it away.
• •Upcast rarely: 9th slot gets 20d6 max (avg 70), but that's Meteor Swarm territory without the multi-area.

Rules Notes

• •The bead lingers at a point and only increases damage by 1d6 at the end of your turn if not detonated, capping at 18d6 after 6 turns (1 minute).
• •Touching the bead forces a DEX save: fail detonates it, succeed lets you throw it 40 feet where it explodes on impact.
• •Explosion spreads around corners, damages objects, ignites flammables; upcasting adds 1d6 base per slot above 7th (e.g., 9th slot: 14d6 base).
• •No line of effect needed after placement; RAW, it works through total cover since it spreads around corners like Fireball.
• •Concentration required until detonation; ending it early (your action? No, as a free choice when you decide) triggers boom.

Synergies

• •Contingency to auto-cast on entering combat, freeing your action for setup.
• •Invisibility or Greater Invisibility to place undetected, then hide while it ramps.
• •Wall of Force or Resilient Sphere to contain enemies near the bead until ready.
• •Slow or Web to cluster foes, then detonate for full AoE value.
• •Familiars/Stealthy allies to 'accidentally' touch and redirect the bead into clusters.

Anti-Patterns

• •Detonating on turn 1 for just 12d6—worse than upcast Fireball with no concentration tax.
• •Placing in open fields where enemies spot and Dispel it immediately.
• •Ignoring fire resistance/immunity common in high CR foes (dragons, devils).
• •Forgetting the bead's visibility makes it a giant glowing target for Counterspell.
• •Using in underwater fights—fire doesn't work well (DM fiat often halves or negates).

Tactical Modules

• •Ambush Trap — When to use: Pre-combat scouting reveals enemy patrol routes or camp chokepoints.. Synergy: Cast under Invisibility, pair with Glyph of Warding for multi-trap denial; ramps to 17d6 while party positions.
• •Cluster Bait — When to use: Enemies are spread but will converge on a point (e.g., fleeing to boss).. Synergy: Synergizes with Hypnotic Pattern or Fear to herd them into 20-ft radius; detonate after 4 turns for 16d6 avg 56.
• •Escape Boom — When to use: Party needs to break contact and flee.. Synergy: Throw bead via ally touch into pursuiters, then Dimension Door away; beats Fireball's immediacy with delay.
• •Boss Phase Shift — When to use: Fight has phases where adds spawn in fixed spots.. Synergy: With Bigby's Hand (if sorcerer twinned somehow) or Forcecage to hold; max 18d6 shreds minions.

Countermeasures

• •Threat: Enemy caster with Counterspell or Dispel Magic — Response: Cast from 150 ft max range, behind cover; use Subtle Spell if sorcerer.. Fallback: Detonate immediately for base 12d6, pivot to Fireball slot.
• •Threat: High DEX foes or Evasion rogues evading touch/throw — Response: Place in unavoidable path with Spike Growth or Grease.. Fallback: Switch to single-target Disintegrate.
• •Threat: Fire immune/resistant boss packs — Response: Scout first with Arcane Eye; avoid entirely.. Fallback: Plane Shift or Banishment.
• •Threat: Bead gets thrown back at party — Response: Position safely outside 20-ft + throw range; have Absorb Elements ready.. Fallback: End concentration early if risk high.

Frequently Asked Questions

is delayed blast fireball good in 5e

Situational—excellent for traps and ambushes ramping to 18d6 (avg 63 fire damage), but poor for instant needs due to concentration. Prep if you're patient; skip for Fireball upcasts in most fights.

delayed blast fireball vs fireball 5e

DBF beats upcast Fireball (12d6 at 7th) if ramped 6 turns to 18d6, plus throwable; Fireball wins for no conc, immediacy. Use DBF for delays, Fireball always.

can you twin delayed blast fireball 5e

No, Twinned Spell requires single creature target; DBF targets a point. Metamagic waste—use Quickened for double actions instead.

does delayed blast fireball work underwater 5e

RAW yes, as fire spells like Fireball do (spreads around corners), but DMs often rule reduced/no effect. Avoid aquatic fights; scout first.

delayed blast fireball maximum damage 5e

18d6 at 7th level after 1 min (12 base +6d6), avg 63 or half 31.5 on DEX save. 9th slot max 20d6 avg 70.

best classes for delayed blast fireball 5e

Wizards excel with Contingency/Illusions for setup; Sorcerers via Subtle/Quickened but conc limits metamagic. Evocation subs boost both.

delayed blast fireball combos 5e

Synergy with Invisibility (stealth place), Wall of Force (contain), familiar delivery. Contingency auto-cast for surprise nukes.

is delayed blast fireball concentration 5e

Yes, up to 1 min concentration required until detonated. Breaks on damage/fail save; plan protection.

Citations: api:spells/delayed-blast-fireball

Includes SRD content per CC BY 4.0. Source: dnd5eapi.co.