Could this be balanced if it didn't add a poison counter? Then it'd require comboing with other poison cards, which
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doesn't have in-element. This would assume that Neurotoxin can only be applied to a target with a poison counter already
Dune Scorpions benefits over this would be reapplying Neurotoxin after the opponent uses Purify, and adding a poison counter on every hit. Whereas this wouldn't require attack raising effects
NB
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and
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, elements with poison, don't have attack raising effects