I agree, I breifly read what they are about and seems like you need water to harm them. Maybe DD can just spit and piss on it alot idk... anyway I doubt DD has much trouble.
How about the Hulk KIller Humanoid... DD get his ass handed to him, maybe...
No. He would adapt-on-the-fly.
Meaning HP DD would gain water abilities or some kind of exotic power to counter them, or his body would turn into something that insulates electricity.
Unless any of them has time manip powers to send him back to entropy, or one of them is at least high Skyfather-level, no one will permanently put him down.
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