while I'm trying to keep largely to clean-up duties I think I have to push for this because I feel it is a deep injustice that this character has not been added to Pure Evil by now.. Brian Banner is the father of Bruce Banner, who is also known as the Hulk.. he is the reason Hulk exists and is possibly one of the most vile, evil men in fiction.. I know this is a hyperbole statement but in this case I feel it is more than justified.
Brian was a horrifically abusive and cruel man who believed Bruce was a monster and would relentlessly harm him on such a colossal level Bruce developed extreme Dissociative Identity Disorder - for those who aren't aware DiD, while still very controversial and unknown, is believed by those who acknowledge it as being formed from not just abuse but prolonged and exceptional abuse.. in short to make a child develop DiD you have to degrade and torture them to the point their mind fragments, that in itself is a dubious "achievement" even in the cruel realms of abuse.
Brian takes this to a whole new level, he murders Bruce's mother in cold blood and openly blames Bruce for it, he continues to abuse Bruce and even after his physical death he returns many times to feed on his son's deep rooted fear of Brian, as well as Bruce's hatred for himself.. which Brian caused.
What can Brian do to top this? how about Immortal Hulk - where he separates Hulk and Bruce entirely, uses Bruce as a battery to power the gates of Hell itself so that the One Below All (God's evil half in Marvel) can enter the physical multiverse.
Brian happily seeks to end the entire Marvel multiverse while still torturing Hulk and Bruce over being "monsters" - he also coldly mocks Creed (Absorbing Man) after Creed corners him and confronts him over his abuse, stating his own father also abused him : Brian finds this all amusing.
Brian's last moments (so far) were spent yelling that Hulk was the real monster and basically declaring himself innocent of any wrong-doing, even though he had been sadistically aiding the One Below All for the entire arc.. Hulk happily (and literally) slapped Brian back to Hell.. however knowing Brian he'll be back in the future and at this point I really think he's earned Pure Evil status as the embodiment of abusive parent cranked up to eleven.. even by comic book standards.