My ninjutsu-
Close to how the Aburame weild the Kikaichu, but a mutated version of spiders that fly. They are summoned similuar to the kikaichu beetles from the host body, and the spiders can survive off of chakra and other insects. They are very very small but once a female spider is released from the body, she can burrow in the ground and spawn babies that rapidly hatch (like kidomaru's summon). Each spider would have enough sleep venom to put a large dog to sleep. So it would take about five bites and unless you have a prepaired anti venom then you are done for if bitten.
I would combie this with an earth style jutsu that would a allow me to make small tunnels underground that the spiders could use to surprise the enemy. Also I would use earth style spider clones to explode. So I could send 1000 baby flying, exploing spider clones over a large area, and blast that area off the face of the earth. If the person survives then the actual real spiders ambsh from below causing instant sleep. Also the spiders all leave drag lines behind that can help with detection. They produce webbing but it would only be used after the enemy was asleep as a powerful rope.