What is HtD's poison ability?

I was looking through the 5* crystals in the incursion's store hoping a 5* Zemo was there. While he isn't, I found Howard the Duck in the poison crystal. Any insight why? I looked at his abilities in case I missed something, but I don't see it.

I'm also bummed that there aren't incursions right now too.

I'm also bummed that there aren't incursions right now too.
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Dr. Zola