Like I said, relatively faithful. Since there's only 4 issues of the character as a title character there's not a lot there. The changes that they did make were actually to add more story rather than take stuff out.
The ghost gets a name and a way more Jason Sudakis style personality, kind of prefer it to the weird stoic comic book ghost. Rather than the ghost being there for Hit Monkey's journey he's convinced that he needs Hit Monkey to finish his business. The arguments between Hit Monkey and Bryce (the ghost) are pretty fun, mostly because they don't subtitle HIt Monkey unless he's talking to other animals.
They also complicate the revenge story and add a bunch of characters. Instead of Bullseye it's Lady Bullseye because they're doing a whole...thing with that character that's different than Bullseye, but Bullseye was the main villain/foe in the comics. They also use a few other Japanese heroes and villains...meaning that the Hit Monkey cartoon had more Marvel characters in it than the original comic. Silver Samurai appears in the finale, Fat Cobra (one of the Immortal Weapons from the seven cities of heaven-one of which is K'un Lun, where the other Immortal Weapon hails from Iron Fist. Fat Cobra is the immortal weapon of Peng Lai. Yuki looks like the ninja Yuki and acts like the goddess Yuki, but this time protects Japan.
I mean, if you watched it you know that and if you didn't you probably didn't click the spoiler...ah well.
The ghost gets a name and a way more Jason Sudakis style personality, kind of prefer it to the weird stoic comic book ghost. Rather than the ghost being there for Hit Monkey's journey he's convinced that he needs Hit Monkey to finish his business. The arguments between Hit Monkey and Bryce (the ghost) are pretty fun, mostly because they don't subtitle HIt Monkey unless he's talking to other animals.
They also complicate the revenge story and add a bunch of characters. Instead of Bullseye it's Lady Bullseye because they're doing a whole...thing with that character that's different than Bullseye, but Bullseye was the main villain/foe in the comics. They also use a few other Japanese heroes and villains...meaning that the Hit Monkey cartoon had more Marvel characters in it than the original comic. Silver Samurai appears in the finale, Fat Cobra (one of the Immortal Weapons from the seven cities of heaven-one of which is K'un Lun, where the other Immortal Weapon hails from Iron Fist. Fat Cobra is the immortal weapon of Peng Lai. Yuki looks like the ninja Yuki and acts like the goddess Yuki, but this time protects Japan.
I mean, if you watched it you know that and if you didn't you probably didn't click the spoiler...ah well.
Non-spoiler stuff-but still a bit much to scroll by if you don't care.
THe faithful stuff was cool, the added stuff was an improvement. The animation style seems more western influenced by Japanese rather than Westerners just doing Japanese style art. I rather liked it. Crazy violent but also light. It's deep in Marvel but not even hinting at being in the MCU, it's very clearly in its own universe. Obviously. Even more-so than M.O.D.O.K.. I liked it overall. I got into Hit Monkey backwards because he was in the Howling Commandos series. I think it'd be cool if they do a second season that they eventually just work it into the Howling Commandos. There's no way they're saving that for the MCU. A team up between a Dum Dum Doogan clone, a zombie Hydra guy...gah, what's his name? Sitwell. Zombie Sitwell. Hit Monkey, Man Thing, Orggo (a big...thing...with glowing eyes), Teen Abomination, Manphibian...that ain't happening in the MCU. I dig that series but I think I'm the only one. I'm a sucker for Man Thing though.
Anyway. Going to be very much to taste. I wouldn't say required viewing but you know, if a mutant (implied) monkey that learns to be an assassin by the ghost of a hitman and gets involved in Japanese political intrigue via a lot of gruesome killing and quippy dialog sounds like something you'd enjoy, you'll probably enjoy it. If that sounds grating as hell it's not going to change your mind.
Anyway. Going to be very much to taste. I wouldn't say required viewing but you know, if a mutant (implied) monkey that learns to be an assassin by the ghost of a hitman and gets involved in Japanese political intrigue via a lot of gruesome killing and quippy dialog sounds like something you'd enjoy, you'll probably enjoy it. If that sounds grating as hell it's not going to change your mind.