Simple enough, form the balls and throw them with as much power as you can, they dont have to be thrown you can slam them into people, each set of balls(eww) so 2 is equal to a B rank, you can continue to use this technique for as long as you have chakra and continue to throw them. If you throw ten balls its essentially 5 B ranks
Castiel gathers and releases his meiton chakra around him, using shape manipulation he forms the chakra into 2 dark release chakra balls, using his brute strength he throws the balls towards that tree over there. The balls explode on impact, causing burns to the tree.
(Meiton: Kuro Renda) Dark Release: Dark Barrage.
Type: Defensive
Rank: B rank
Range: Short-Mid
Chakra: 20(+10 for every extra shot fire)
Damage: 40
Description: The user will begin by holding both his hands up with the palms facing towards the sky. The he will condence dark chakra inside his body and cause it to seep out of his palms and form small balls of dark chakra around the size of a cannonball. Then by using brute strength the user will throw the balls at the opponent. Upon impact the balls will explode into a maelstorm of dark chakra severely burning the opponent. This jutsu isn't limit to just two shots as the user can continually form and throw these balls. The balls form rather swiftly about the same speed as a chidori. Each 2 balls are equivalent to a B ranked Dark release technique.
Can only be taught by Delta
Good enough?