Good thing he practiced dropping and reforming them quickly.

Karasu sprays a stream of poison gas at Shino.

Who turns into a person-shaped mass of bugs that quickly disperse. A few bugs that're caught drop dead.

It's unclear where the real Shino is.

That's a problem. Is there any sort of center to the bugs' movement?

Nope. 

The swarm's focusing mostly on him, though there's a good bit of fowling up Karasu's strings going on.

A few black dots, easy to miss, are crawling rapidly across the ground, easier to avoid but harder to notice. In fact, the swarm might be trying to herd him towards them.

Isn't that interesting. Smells an awful lot like a trap.

He maneuvers Karasu to a mostly-free spot, and does a quick transform-and-replacement under cover of snapping his strings to shake off some bugs. And then the puppet can be the one to take the trap.

The bugs notice the switch, though Karasu does end up with a few more passengers.

Tsk. He'll vent some gas to kill them.

That works for most - 

But not all, and the ones that don't drop dead from the poison seem to be multiplying.

That's a problem. He needs to find the controller. The arena's not that big, right?

Not very.

And those trees are the best bet... Okay. He can run a search pattern, looking for places the insects respond more strongly as well as normal tracking signs. And rely more on Replacement to get out of trouble than poison.

The insects don't seem to be responding to any areas more strongly than others. There's a bit of disturbed earth over there, but not much else in terms of signs.

And if Karasu walks over it?

Nothing.

Not a trap. Earth Walking? Explains why he can't be found. Expensive jutsu in terms of chakra, though. He might be able to outlast up here, wait for him to surface.

In the meantime, he should work on reducing the number of bugs around. Skipping the poison, he has Karasu roll to crush them.

The bugs are mostly able to get around that.

There's still a lot of them, and they're moving now so that it's hard to dodge out of the way.

He uses all of the considerable stealth skills he has, buying more time.

Stealth doesn't really work against the bugs, and they're smart about circling around him and sneaking from behind.

Shame to go without even seeing his opponent. He slips a rebreather on, and drops one of his other poison bombs.

That one's more effective than the last.

The clouds of bugs are definitely thinning.

Good. Any sign of him surfacing? He's a fresh genin, can't have that much chakra.

The fight drags on for a bit more, but - 

Shino does eventually surface, saying "I forfeit. Why? I am low on chakra, and would not have enough for the next fight." He inclines his head towards Kankurou, then walks towards the waiting room.

Sure, that's one way to do it. He wraps Karasu back up and heads upstairs.

"You won."

"You don't have to sound so surprised about it."