| glum(adjective, evil, mysterious, threatening, nefarious) |
| hellish(adjective, evil, mysterious, threatening, nefarious) |
| horrible(adjective, evil, mysterious, threatening, nefarious) |
| immoral(adjective, evil, mysterious, threatening, nefarious) |
| indecipherable(dark, uncertain, mysterious) |
| infamous(adjective, evil, mysterious, threatening, nefarious) |
| infernal(adjective, evil, mysterious, threatening, nefarious) |
| inscrutable(dark, uncertain, mysterious) |
| intentive |
| intricate(adjective, evil, deep, mysterious, hidden) |
| kiss-and-tell(adjective, telltale) |
| knotty(adjective, evil, deep, mysterious, hidden) |
| nasty(adjective, evil, mysterious, threatening, nefarious) |
| nefarious(adjective, evil, mysterious, threatening, spooky) |
| not known(expression, adjective, evil, deep, mysterious) |
| not missing a trick |
| predicting(adjective, obscure, significant, wise, vague) |
| prognosticative |
| satanic(adjective, evil, mysterious, threatening, nefarious) |
| scowling(adjective, evil, mysterious, threatening, nefarious) |