Yamato creates water and earth chakra inside his body, combining and mixing them to create Moku chakra. After doing this, Yamato focuses the newly created wood chakra into his hands. He releases the chakra from his body while using shape transformation to create two small wooden kunai in each hand. He then throws them all at the training dummy.
Advantage:
It is a quick way of obtaining kunai
Disadvantage:
The kunai probably won't be able to reach long range
Can I create any amount of kunai I want with this jutsu?