My opinion about who is the most terrifying:
The nightmares, The umbrums and the pony of the shadows.
The nightmares take the 3rd place, because they are not so scared, they work well as a team, but without a leader they do not work well.
The pony of the shadows takes the 2nd place … because ?, it is true, he is the first villain where he faces 12 heroes, and has a good background story, but he did not do much in the whole episode. And also he needs a host to maintain his physical form.
And finally, the Umbrums, they take the 1st place, the truth does not need explanation, just look at it !!!, I feel that they would surpass all the villains, one is dangerous, and they work in groups and can block magic, etc.
Well … that's my opinion, what do you think?
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