comparing the christa pike murder it's one thing to murder one person horrifically but to do it at an industrial scale that's however another thing.

One murder, however horrific, is one person's decision in one place and time.
What the Nazis did was turn murder into an industry. They had departments for it — people to design the camps, people to schedule the trains, people to produce the gas, people to keep the lists. It wasn't rage or a fight gone wrong. It was factories, timetables, and bureaucracy built for one purpose: killing millions of people as fast as possible because of who they were.
like how horrific can you get when the nazis were manufacturing mass killings and burning people alive and gassing and torturing millions of jews and killing them?