I honestly thought adding epic raw blood BRUTAL KILLS BRO titty dongs made the game more childish instead of mature or whatever.
In Mega Man Zero, I mean.
It was also pretty stupid in Lords, though, like the game expected me to high five the screen and say 'whoa dawg this is brutal shit, Mom and Dad don't want me to play this game but I'm gonna!" Blood and gore is, like A-yty-sama said, a gimmick. It was shocking and adult and mature and bullshit in '93 with DOOM and Mortal Kombat. Seeing it applied so hamfistedly just came off as unintentionally comical, much like the dumb attempt at internet humor with the cake note.
But anyways, the series was never mature or even bothered to strive to be "raw". All the way through Chronicles, the series just strove to be a homage to the cheesy 30's and 40's Hammer Horror flicks. CV1 was definitely humorous, what with the film reels flanking the title screen, the corny enemies and music, and the pun names for the credits. And that's a huge factor in the enjoyment of that game.
Even Chronicles' Arranged CGI opening flickers and has fake dust and dirt effects to make it look like it was shot in the 30's.
Anyways, a series resorting to bland 'shocking' things like nipples and blood doesn't signify maturity. Instead it signals zero creativity. It's just telling pre-teen kids that if you own RAW EPIC ACTION TIT BLOOD GAME LORDS then you're a cool edgy badass! All your base are belong to us! Cox wears baggy pants exposing his boxers, too! Adult!