The wording of the card is a bit unclear. So the target doesn't deal damage to the opponents but deals damage to adjacent creatures instead? If this is not what you mean, then I would change the word "attack" to something else. Also, by "adds 1 poison damage to target creature," do you mean "adds one poison damage to target creature's attack?" If so, I would change the wording to "target creature gains 'venom' as an active skill." This would serve as a good balance mechanism as well, because then the creature (and adjacent creatures) would no longer retain their original active skills. If this is not what you mean/want, disregard it though.
I like the theme of the card though.