After performing the two hand seals, I create an enormous shark, at least 100 times bigger than myself. The shark is pretty much taking up the size of half the lake it's that big, and so I send it to eat the clone, absorbing it's chakra and thus killing it.
This is an enormous technique, meaning it takes time to form, even for someone who clearly specialized in Water jutsu like Kisame. When it absorbs chakra, two noticeable things will happen: first it will devour the technique, rendering it to nothing so the shark can continue. Secondly, the shark will grow larger and by extension more powerful due to the chakra filling the shark with more of what it desires and so on. I'd assume this technique is closely based on the Samehada sword which explains how it works. In term, the shark grows bigger and stronger eating techniques, which helps defend against larger jutsu.
I have a question, do elemental advantages count towards the shark absorbing chakra? So it would only absorb up to C-Rank Earth and A-Rank Fire?