9. Kraven The Hunter
First appearing in the pages of Amazing Spider-Man #15 (1964), Sergei Kravinoff (Kraven The Hunter) is a big game hunter who aims to kill Spider-Man so he can prove himself as the ultimate hunter. Half-brother to the Chameleon and a founding member of the Sinister Six, Kraven he often regarded as one of Spider-Man's most formidable enemies.
Kraven is an Olympic-level athlete at peak human condition, an expert in hand to hand combat and gifted hunter and tactician. Alongside his knowledge of pressure points in both humans and many animals, he could disable anyone with ease. Furthermore, his use of exotic poisons and tranquillizers give him an edge over opponents much more powerful than he is.
Recently Kraven demonstrated his skill in Nick Spencer's Hunted (2019) storyline where Kraven hunted and captured every animal-themed character in the Marvel Universe including Spider-Man himself as part of his 'Great Hunt'.
Fortunately, for the Marvel Universe maintains a code of honour, preferring to treat his adversaries as equals. Otherwise, he would be able to track down anyone he wanted and kill them without them knowing he was hunting them, giving the Punisher a run for his money.