90s Possible Cereal Prize books about monsters

Been bugged by a memory of reading little miniature illustrated books in my early childhood of examples of media and mythical monsters. Had lovely/gruesome artwork I would love to see again. I think there was more than one.

Was probably the late eighties to late nineties in the uk. I think they were cereal prize pocket books or something similar. Each page spread had a colour painting of the monster along with a bit of reference. Seemed almost like it was something a kid shouldn't be looking at.

Remember the Hydra, with a description of having to cut the heads off and burn the stumps. Pretty metal to read when you were a kid. Had a page about zombies with a very moody artwork of slimy corpses coming from ground. Mentioned night of the living dead.

One page had a monster with the face clearly traced from the monster from 'Fright Night' that stuck in my head because I recognised it.