@humbleoverlord It's mistranslated. The water is colder than air's temperature. So it's like a short term refrigerator. It's an actual preservation technique that hunters use.
It's time for guillotines, it's time to raise the boards
It's time to sharpen blades, we just can't take this any more
It's nothing personal, we gave your way a try
We're sorry, but you at the top all have to die.
She should've informed him about how she upgrades the targets to match his level. He's dumb for not listening to his teacher, but she's ultimately at fault for making him believe he was at far lower level than he actually is. Imagine if he tried to use that against someone who wasn't overpowered...