Without the use of hand-seals, the user will form a collection of burning ash in their hand and throw it at high speeds. Upon contact with a solid object, the ash will explode into a small (one meter in diameter) of burning hot ash. It can cause minor burns and cause intermediate damage to eyes and respiratory system.  A clean hit blinding a person until they are able to receive medical attention.  Alternatively it can be used to ignite flammable objects or set off traps.  The jutsu can be used in quick succession but is not overly lethal.