Spellcasting and interactions with S/M components when hands are in use

Question

Let's say I've got a creature who has a shield in one hand and their focus in another. They also have the war caster feat

They'd like to cast a spell requiring a Material component with cost/that will be consumed and a somatic component.

What does the caster need to do in order to successfully cast this spell?

The way I've always understood if its a spell that needs a costly material/material consumed then you would have to drop something in order to give you a free hand to access the materials.

To give more clarity for this issue, here is a specific example. I have a high level wizard at my table, who has taken the war caster feat, they also have proficiency with shields. In one hand they wield a shield, in the other they carry their arcane focus of a wand. They cast the 6th level spell, Circle of Death which has the following Components: V, S, M (the powder of a crushed black pearl worth at least 500 gp). At the table I allowed the cast to go through as the wizard had previously obtained the crushed black pearl dust of the appropriate value. My question becomes, should I have required the wizard to drop/unequipped the shield so that he could of accessed the pearl dust from his backpack/component pouch.

Answer 1

In order to cast the spell, the character needs to stow either their wand or shield (the wand makes more sense) and retrieve the pearl dust from wherever they have it stowed. How long this takes is up to the DM, but in my experience, most DMs will allow it as a free interaction.

The spell has Somatic and Material components, and as you note in the question, the rules do not allow those material components to be satisfied by a spell focus. So the character needs at least one hand free to perform the material component of the spell. Since the presence of a specific spell component removes the need for the spell focus, getting rid of the wand is the most obvious choice.

War Caster specifically allows the character to "perform the somatic components of spells even when you have weapons or a shield in one or both hands", but this doesn't help here because War Caster feat only removes the requirement for somatic components to require a spare hand, not material components.

Stashing a wand in your belt, and retrieving a spell component from whatever pouch a wizard has it stashed in, are generally ruled as free interactions that can be done on your turn of combat without using up your action or bonus action. However, the cost of doing two such interactions on your turn is ambiguous, much like the cost of swapping weapons. A DM might rule that swapping a wand for some pearl dust is a single, free interaction, or multiple interactions that together use up your action.

As I said above, in my experience most DMs choose the former.

The only exception is if the spell component is in some hard-to-reach place that is definitely going to take an action to find, like the bottom of a backpack, but once again most of the time it's assumed that casters keep components for in-combat spells in convenient locations.

Answer 2

Have one hand free

If a spell states that a material component is consumed by the spell, the caster must provide this component for each casting of the spell. A spellcaster must have a hand free to access a spell's material components -- or to hold a spellcasting focus -- but it can be the same hand that he or she uses to perform somatic components.

That free hand can do the Somatic and access the Material components including both the focus/spellcasting pouch and any costly component(s).

Why this spellcaster is holding their focus is beyond my understanding - they don't need to, they need a free hand to "access" it. Keeping it on a chain around their neck or in a pocket makes more sense but you do you. Notwithstanding, given that the PC with the shield and focus has "one hand free" (but for the focus), they are good to go.