Polymorphism
In X-Men #191, when confronting Wolverine, one of the Children of the Vault named Serafina claims that adamantium has thirteen allotropes, all of which are "unstable, and short-lived, but virulently poisonous." She throws a small device that clamps onto Wolverine's claws and makes them glow green, claiming that it is adamantium nine. This apparently raises adamantium's toxicity dramatically, overloading Wolverine's healing factor. However, allotrope is a misnomer, as Adamantium is an alloy and not a pure element. The more general term, used for any crystalline material, is polymorphism.
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