Dan of the Slow Mo Guys had never used a katana sword before, but he did a great job using it to slice 10 plastic bottles of water in half. He said it felt like he was slicing butter.

He also slices through jumbo bottles of colored liquid, which doesn’t look as tricky (who am I to say?!) but makes a pretty picture.

from Boing Boing https://boingboing.net/2017/11/14/watch-a-katana-sword-slice-thr.html