Death

isn't this faster?

Not really faster since they have to learn the rules and limits of the notebook. Meanwhile, a knife is simple, aim, and push forward.

Decrease the time you say?
ZA WARUDO!

The Death Note can cause any death method.

Yes, but forty seconds to call for help vs keeps stabbing until they stop moving. My money is on the knife.

Wrong. Write "dies of issues in voice box as soon as possible".

Wrong, never once could Light decrease the amount of time. He could increase the time, sure, but never decrease. Besides as soon as possible would be an even worse way to word it as it might take even longer since the book's logic on time is decided solely of the death god holding it, not the human using it, so unless the specify exact time it won't matter, Light figures this out long before even meeting his Death god.

Let's make this into a wholesome note

Yah he's the paradise reaper

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