Dante’s Grimoire: Eldritch Blast
A beam of crackling energy streaks toward a creature within range. Make a ranged spell attack against the target. On a hit, the target takes 1d10 force damage.
At Higher Levels. The spell creates more than one beam when you reach higher levels: two beams at 5th level, three beams at 11th level, and four beams at 17th level. You can direct the beams at the same target or at different ones. Make a separate attack roll for each beam.
Eldritch Blast is one of the few spells afforded only to Warlocks. It has quite the reputation with it, affording some of the highest damage per turn of many spells, and the highest damage per turn of any cantrip in 5e. This all makes it a prize for anyone to take. It is also highly adaptable given its connections to Eldritch Invocations, which I will discuss in a moment.
Given the hinderance of the warlock class at all levels of play, that being too few spell slots, cantrips are an incredibly important choice for these casters to make. Due to this, you would be hard pressed to find a warlock at high levels that doesn’t know this spell better than any other.
Eldritch Blast deals 1d10 force damage per blast, and the caster can send more blasts down range as they level up. Force damage is a great investment for damage as in all of officially released 5e, there are only 9 creatures that resist it and 5 that have immunity to it. This is rare, as fire immunity is incredibly common at later stages of play, much like poison, acid, and cold. Force damage hits hard more often than higher damage spells.
The use of Eldritch Blast coming in multiple attacks as opposed to one attack that gets more powerful comes from the math of Dungeons and Dragons. Without advantage or the Hexblade’s Curse feature, the odds of a critical hit using spells like Firebolt at max level is 1/20. For Eldritch Blast, that probability goes up to roughly 1/5. More attacks means a better chance for a hit. This means that a caster will hit more often each turn and dependably do more damage than a spell that either hits or doesn’t.
Now, let’s talk about the system that makes Eldritch Blast very powerful in the hands of a warlock, as opposed to say a wizard that took the spell with a feat: Eldritch Invocations! There are 5 invocations that can adapt Eldritch Blast at a moment’s notice if need be: Agonizing Blast, Eldritch Spear, Grasp of Hadar, Lance of Lethargy, and Repelling Blast.
Agonizing Blast allows the caster to add their Charisma modifier to the damage of each and every hit with eldritch blast. With a maxed charisma, this can mean up to 20 additional damage every turn. Compare this to abilities like Empowered Evocation or Elemental Affinity which allow the modifier to be added to one damage roll for a spell. This means that with one evocation, this spell can now compete with the fighter’s longsword or the ranger’s longbow. This is the invocation that I would recommend most highly.
Eldritch Spear takes the normal range of the spell, 120ft, and more than doubles it to 300ft. With one simple addition, this cantrip can now compete with martial ranged weapons like the longbow or the heavy crossbow; weapons that require proficiency for other classes to get this kind of range for engagement. When going up against fast opponents like a monk or the fey Quickling, this ensures that the target can’t simply get out of range every round. If your warlock is a bit ruthless, this invocations is also a great boon.
Grasp of Hadar acts like a lasso, pulling the target up to 10ft closer to the caster. This is particularly useful if the player is a Hexblade tank for the party, or if the warlock uses the Pact of the Blade and wants their victim to be constantly within range of their pact weapon. This invocation is reminiscent of the monk’s Open Hand Technique that also allows the player to keep the opponent where they want them. However, a monk must use Ki points to use this feature, whereas a warlock doesn’t use any resources.
Lance of Lethargy is used as a debuff, knocking the target’s speed down by 10ft until the end of your next turn. In the same light as Grasp of Hadar or Eldritch Spear, this is best used to keep the enemy in range and maintaining constant damage going down range. Once again, this is best used on quick opponents or in tandem with the Sentinel Feat.
Repelling Blast is the opposite of Grasp of Hadar. Instead of pulling the target closer, it pushes them back. This is useful for an inverse reason, keeping targets away from the squishy, d8 hit die warlock. If your warlock is more of an intellectual caster, it is best to keep say the half dragon warlord away and using spells like fireball to do damage from a good distance.
I can’t recommend taking all five of these invocations as even at Level 20, there is a maximum of eight or nine with a feat. Given the fact that you can only use each of the final three once per turn, it isn’t useful for pushing or pulling something more than ten feet, or knocking a target’s speed to 0. It simply comes down to the logistics of the game.
To wrap up, Eldritch Blast is one of the best spells a warlock can take, offering consistent damage that rivals a fighter. If used in tandem with concentration spells using your pact magic slots, this spell can be used to great effect on targets, dealing unavoidable damage and keeping the heat up in long fights. So please, if you haven’t, try Eldritch Blast in your next campaign and use it wisely.