i cant get past the satana fight. is there some kind of mode where i can change to? i cant get him to even 500 hp. i have to spam hamon hair.
You could grind for exp in the desert, but if you don't have a save file before entering the German base, I'm afraid you can't do anything about this. I can make an update to the game in a few hours that can fix that issue.
UPDATED: Now you can leave the base before the fight and level-up to get stronger. I also recommend stocking up on healing items.
You might have to start from the begining tho, sorry about that.