In the D&D for dealing with spellcasters is the silence spell, as it shuts down the ability to use most spells.
Spellcasters in D&D wield incredible powers that allow them to match the might of dragons. This power comes with restrictions, such as getting the drop on a spellcaster and holding their arms, which drastically reduces the number of spells they can use. That's why spellcasters need their meat shield and healer friends around, otherwise, their adventure would end in a single round of MMA-style combat. Technically, the Grappled and Restrained conditions don't outright state that spellcasting is impossible, but it's ambiguous.
D&D principal rules designer D&D's powerful enemy spellcasters is by preventing them from talking, but this is often easier said than done. A spellcaster doesn't rise through the levels by being stupid, which is why many of them protect themselves with defensive magic, or with waves of minions. If the spellcaster can be silenced, then their power decreases dramatically, as they will lose access to most of their spells.
The Dungeons & Dragons Spells That Can Be Cast While Silenced Or Gagged
These are the spells from the Dungeons & Dragons Player's Handbook that can be cast while gagged. These spells have no verbal component, which means the caster simply needs to be able to move one hand to use them. There are significantly fewer spells that can be cast while silenced than bound, which shows just how effective it is to gag an enemy spellcaster. Many of these spells belong to D&D's illusion school of magic, as it would break the effect if the caster was seen actually performing the spell before the illusion appeared.
- Cantrip: Minor Illusion
- Level One: Friends, Illusory Script, True Strike
- Level Two: Beast Sense
- Level Three: Counterspell, Hypnotic Pattern
- Level Five: Mislead
- Level Eight: Demiplane
The spellcaster players who are gagged lose access to most of their repertoire, with illusions being the best option for escape. The sorcerer class has a built-in way around this problem, thanks to their Subtle Spell Metamagic ability, but there are a limited number of times this can be used, so they will have to carefully consider their options before burning through their Sorcery Points. The addition of D&D's powerful counterspell isn't too surprising, as it was established that counterspell can counter another counterspell, so it couldn't have a verbal component of its own, making it one of the most useful spells in Dungeons & Dragons.
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