1 ideas

hunter x hunter(killuas brother),

highschool dxd(half angel half demon),

dragon ball(frost demons)(cell)(majin buu race),

bleach(hollow/shinigami),

reincarnated as a slime(a slime or dragon demon),

overlord(nephilim or dragon),

demon slayer( demon with sword abillites),

marvel cinematic universe( thors older brother),

arrowverse the flash( kryptonian whos ship went to world 1 and became the flashes brother kryptonian speedstar),

harry potter(son of grindelwald or voldemort or dumbeldore),

my hero academia( todorokis twin),

fairy tail(zeref's son)

naruto(madaras twin)(madara son)(narutos twin)etc

one piece(whitebeards biological son)(kaido and big moms son)

helsing(alucards brother)(integras brother)

Danmachi(bells twin)

sao(asunas brother) (kiritos brother)

lucifer show( lucifers son)(a arch angle)

mob qsycho( mobs twin brother)

one punch man ( tornados brother)( saitamas brother)

supernatural(michals son before canon)(lucifers son befor canon and jacks half older brother)

ps. system if possible or a status screen if not a power ranking system at the beigining or not

update: this fanfic is dropped but if there is a author out there that is willing plz continue its a DBZ fanfic. https://www.webnovel.com/book/13858307506800905/Dragon-Ball-%3A%3A-Drago-Sercles%5B-AKA-Dragon-God%5D-with-*HACK* the previous author is sercles