Oh okay.
The most messed up thing Newt has done is kill her own half sister, use her magic to command her dead body like a doll, and then gaslight everyone else into thinking that they were fine and they just ran off.
Either that or the time she made a deal with a mysterious entity (not Entity, a different entity. Notice how the first one has capitalisation but the second doesn’t.), in exchange for like power and whatever, and to accomplish said deal she killed a guy and did some other messed up stuff.
But in comparison to what he did, it’s really not that bad.