How do multiple beams of eldritch blast work with a Pact of the Blade weapon? When I, as warlock, have my Pact of the Blade rapier in one hand and cast multiple beams to hit either single or multiple enemies, do I need to drop/sheathe my sword to do these multiple beams with two hands?
Can a warlock shoot multiple beams from the Eldritch Blast cantrip with only a single free hand?
You need only one hand free
Eldritch Blast has the Verbal and Somatic components indicated by "Components V, S". Looking at the rules for spell components (Verbal is not relevant regarding free hands so not included):
Each spell's description indicates whether it requires verbal (V), somatic (S), or material (M) components.
Spellcasting gestures might include a forceful gesticulation or an intricate set of gestures. If a spell requires a somatic component, the caster must have free use of at least one hand to perform these gestures.
As you can see from this description, only a single free hand is needed to cast a somatic spell. The fact that Eldritch Blast can launch multiple beams does not mean you need more free hands to launch them. Nothing in the description of Eldritch Blast suggests more free hands are needed, the beams are simply launched, so you only need one free hand and can be holding your pact weapon Rapier in the other hand when casting Eldritch Blast
3\$\begingroup\$ I feel the phrase "laser light show" needs to be in this answer as to how all the beams of EB are emitted from a single free hand. Or maybe I'm just dating myself... \$\endgroup\$– cpcodesJul 22, 2019 at 16:14
\$\begingroup\$ "The fact that Eldritch Blast can launch multiple beams does not mean you need more free hands to launch them" - especially considering that at level 17+, eldritch blast produces four beams, and most PCs don't have four hands that would all need to be free... \$\endgroup\$– NathanSJul 31, 2019 at 9:17
Yes, you can.
The spell Eldritch Blast is listed as having Verbal and Somatic Components. Under the rules for Somatic Components, you can see the following rules text:
Spellcasting gestures might include a forceful gesticulation or an intricate set of gestures. If a spell requires a somatic component, the caster must have free use of at least one hand to perform these gestures. (Basic Rules, p. 83)
As a result, as long as your character has at least one free hand, you are able to cast the spell. The spell then does what it says it does, and if you're of a sufficient level, it produces the extra attacks. You do not need to have additional hands free to make these attacks, since it doesn't say that you do.
1\$\begingroup\$ seems legit for me will upvote today later, after completing signup @nick012000 thx. \$\endgroup\$ Jul 22, 2019 at 13:04
warlocktag says it's specifically about the D&D class. (In my opinion that's absolutely wrong and misleading, but I'm waiting to see that hashed out on meta.) \$\endgroup\$