Did you actually took your time to level up the weapons that have passives abilities in them? Did you fought enough to actually lvl up Aries instead of skipping through enemies? You bought the best accessories from the accessories shop in Town? That shop owner even give you a particular good One for free. Etc etc. You do use a good combo rotation? In hell it's important you launch your enemies and kill then while they are in midair Without letting them touch the ground and you Need to lvl up to learn new Attack Combos and improve your combo rotation. I can only possibly think you didn't lvl up enough, also, the counter and getting out of enemies range to try Surprise attacking them Is very important playing in hell, There's even One skill that if used correctly let you phase through the enemy to reach behind them and that Is quite useful to keep moving out of their Attacks and to back attack. If you cannot time the counter and you don't Surprise attack them from out of range/back attack it can be quite hard. The infected boy Is a patience matter, his patterns are very Easy to understand, Just keep moving out when he Is about to Attack cause he does quite High damages but he Is Easy to read.