You’ve got general Thaddeus Ross, was the Air Force general at the gamma bomb test and father of Betty, Bruce’s love interest and eventual wife, a military man who views the hulk as a threat to national security, Ross quickly became obsessed with destroying the hulk well beyond just his military orders, going against the orders from his country for his obsessive crusade.

Samuel sterns, aka the leader, originally a low level worker of average intelligence, after an accident at the facility where he worked caused him to get toxic waste into an open head wound he became mutated, green skin like the hulk but rather then gaining immense strength, his intelligence increased to superhuman levels, as well as his ego as he seeks to conquer the world and remake it in his image, although he eventually learns of something deeper connected to gamma energy and his plans grow more ambitious.

Carl creel aka the absorbing man, originally a Thor villain but he’s fought the hulk enough times he’s kinda considered an enemy to both of them, Carl creel was a boxer turned mob enforcer and low level criminal who Loki gave powers to as a ploy to deal with Thor, creel now has the ability to “absorb” the properties of anything he touches, this can be as simply as becoming metal or stone, but if he concentrates he can absorb more of a vague “essence” of an object, such as absorbing a tank and becoming a human/tank hybrid, his powers are magic in nature so the times are more vague but incredibly dangerous when he gets creative.

But as powerful as creel is he’s not the sharpest tool in the shed, usually he gets beaten because of his own short sightedness, but he’s gotten a redemption arc as of late and is closer to one of the good guys, he’s ahdo happily married to Titania

Xemnu the living hulk, an alien criminal who escaped his prison and came to earth soon trying to conquer it, xemnu possesses extreme telepathic and psyonic abilities, but what’s unique is these powers are stronger when projected through screen based media,

He initially used this by staring in a kids show and hypnotizing a bunch of kids to bring into a spaceship so he could convert them into more of his race to repopulate his planet “all his people conveniently died off panel”

But most recently he teamed up with the CEO of the Roxxon oil corporation, using their vast media empire xemnu put the entire world under his influence by entering their minds under the guise of nostalgia, he subtly influenced their mind inserting himself into treasured childhood memories and convinced the world he was actually the hulk, all the good things hulk had done where him while all the bad things where done by dr banner. You all remember xemnu from the magic planet right? Back when you were young, before life got so hard? Do you remember the smell of a new action figure? Watching Saturday morning cartoons? Then you remember xemnu! And you love xemnu

Emile blonsky aka the abomination, Russian spy why was exposed to a larger dose of game rays then Bruce was, admittedly he’s kinda just another hulk who hulk punches most of the time but he has more interesting stories as well.

Brian banner aka Bruce’s father, now Brian banner isn’t a typical villain given that except for two specific occasions he has no super powers and is dead, but it was the trauma from a childhood of abuse at his fathers hand and witnessing his father murder his mother when she tried to leave that caused Bruce banner to develop dissociative identity disorder, the hulk was a separate personality that banner had long before the gamma bomb, in fact there’s more then one hulk alter in Bruce banners psyche, but we’re talking about villains not the hulk(s) himself/themselves

Bruce banner would end up killing his father accidentally and in self defense as an adult after Brian was released from a mental institution, but even dead in the ground the trauma Brian caused will always hang over Bruce, not to mention the two times higher powers of sorts resurrected him to use against Bruce