Wolfsbane (5e Spell)
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|Casting time:||1 reaction, which you may take when another creature uses a spell or effect to change its shape.|
|Components:||V, S, M (a handful of animal fur)|
Whenever creature uses a spell or effect that would change its form, that creature must make a Constitution saving throw. On a failure, the creature does not change shape and takes 4d6 psychic damage. The target’s action is wasted, and if the shapechanging feature has limited uses, one use is also wasted.