I don’t think that would be RAW, because the hostile creature wouldn’t be leaving the caster’s reach, as required by Opportunity Attack. So the caster has no option to cast in that case, even with the feat that would allow it. Now, if the caster had already cast Shocking Grasp, that could be different. I’d probably let that work because all the necessary rules seem to line up, in terms of actions, Shocking Grasp being a melee spell attack, OA typically requiring a melee attack, and delivery of touch spells being the exception to the ‘familiars can’t attack’ rule.
There doesn’t need to be an opportunity attack for a familiar to deliver a shocking grasp with its reaction. If the wizard casts the spell, the familiar uses its reaction to deliver it no matter what the hostile creature is doing. As long as it’s within 5 feet of the familiar, that’s all that’s really required.
A familiar can't attack, but is it allowed to defend using a reaction?
Cedo nulli, Calcanda semel via leti.
Parvi sed magni.
Which reaction are we talking about?
"Opportunity Attack" is not allowed, because it is still an attack.
IMHO: The character controlling the familiar can attempt to cast Shocking Grasp
Finally, when you cast a spell with a range of touch, your familiar can deliver the spell as if it had cast the spell.
playing since 1986
I don’t think that would be RAW, because the hostile creature wouldn’t be leaving the caster’s reach, as required by Opportunity Attack. So the caster has no option to cast in that case, even with the feat that would allow it. Now, if the caster had already cast Shocking Grasp, that could be different. I’d probably let that work because all the necessary rules seem to line up, in terms of actions, Shocking Grasp being a melee spell attack, OA typically requiring a melee attack, and delivery of touch spells being the exception to the ‘familiars can’t attack’ rule.
I agree, this is the reason why it wouldn't work.
A familiar can’t attack, but it can take other actions as normal, including the Dodge action if it's what you were asking.
There doesn’t need to be an opportunity attack for a familiar to deliver a shocking grasp with its reaction. If the wizard casts the spell, the familiar uses its reaction to deliver it no matter what the hostile creature is doing. As long as it’s within 5 feet of the familiar, that’s all that’s really required.
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