Origami: The ninja kunai

After 2 origami kunai tutorials, many people still have
questions, especially about step 12, 13, 14 etc. etc.
So, I decided to make a tutorial with pictures.
I hope this will answer all people questions,
and that this origami tutorial is clear enough for everyone...

Still have questions? I would be able to help you

-Warning! Large file >.<
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Important: this origami isn't easy, so origami beginners, please practise often if you want the great result
Origami Level:

Want to decide the side of your Ninja kunai?
Here is the formula:

The horizontal side of the sheet you use, would be the total horizontal cm of the kunai, and the vertical side of the sheet, would be shared in 3 parts.
For example:
If you use a sheet of 15 cm by 15 cm,
the harizontal side of the kunai would be 15 cm,
and the vertical side of the kunai would be (15:3) 5 cm

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