They're actually some of the easier segments to beat without damage on Normal mode, as they have predictable behaviors/patterns. The most difficult thing in NG is juggling your focus of offense/defense between multiple enemies (and most importantly, multiple types of enemies, each requiring different strategies). In higher difficulties when minions spawn with the bosses, it becomes more difficult. I'd imagine the safest way would be to use the Inuzama to dispatch most normal minions, and then focus on the boss exclusively.How the fuck do you beat the bosses without damage!¿