Itadori manages to land on one of the snake's heads, riding it like a pony, and goes "Yeeehaw!" as he starts hacking at its neck. It makes an inhuman screechy gargly noise and one of the other heads tries to attack him but he dodges well enough that it has to pull back lest it bite its own head off.

So it decides to change tacks, and all of its tails decide to go for Hayashi in hopes of pinning her down and holding her hostage.

She lets out a little snort at her new cowboy companion, who definitely seems to be having the appropriate amount of fun.

Well, all of the tails going for Hayashi at the same time just makes her feel like she's back on her own. Which is to say: about normal, really. No, Hayashi will not be your hostage for today, and for shame for thinking that! In fact, somebody needs a reminder that she is a sorcerer, not a bystander. And she's been given such an excellent opening, with that head pulling back before it bites itself. She throws several needles, leaps, spins mid-air to get the angle just right, and then sends her projectiles swerving to see about causing some blindness. Then she lands neatly, and gets back to playing keep away.

It's blinded, or at least many of its eyes are, and it starts thrashing wildly this way and that, ironically all the more dangerous for being less targetted and less concerned about its own safety. It manages to shake Itadori off—

—and great timing, too, because a crocodile the size of a truck with far too many eyes and legs emerges from the water (where it definitely had not been prior to this) and takes all of the snake's heads into its unreasonably large maw. It makes gargly ear-piercing noises as it chows down on the snake and tries to eat as much of it as it can before it disintegrates.

Itadori himself has managed to grab hold of a tree branch and used his momentum to swing back to Hayashi's side, and now he's just watching gobsmacked as one curse eats the other.

"That is the curse the domain belongs to," she reports, wrinkling her nose. "Aaaaaand it's now getting a power up from eating its fellow. Great."

Needles in the eyes, crocodile with no setup edition! Can she pull it off? She doesn't have high hopes but blinding it early would be really helpful!

It... it has too many eyes. She definitely cannot blind them all. It seems less protective of them for having so many, too, and when it lands on the muck (with an accompanying enormous wave of swamp water and dirt in all directions) it turns towards them and screams at them (it has a second mouth inside its mouth, and eyes inside that one).

"So I still try to dismember it?"

Oh, ew, it's gross. She's so glad she's a sorcerer and gets to kill it for being gross.

"Yes, please. Let's kill it if we can, but we're stalling until our third gets here. Don't let it tire you out."

"—Senpai you can't give me an opening like that and then ask me not to make any innuendos!" 

That startles a laugh out of her.

"I don't remember asking that. Now I'm curious!"

She says this as she relocates somewhere she'll have a lot of room to move. Because this is still a combat situation.

"I lost the timing! But, you know, we can't have all the fun by ourselves and let our third dry in the field, or something, I dunno." Right, combat. Here's another leap at the thing's head, cleaver first, and—

—it's fast. It dodges out of the way far too quickly for something that size, and then immediately turns its whole body 180 degrees to throw its whole weight into swinging at Hayashi and Itadori with its body and tail (tails???? did it grow a second tail after eating the snake??????).

Fortuantely, she was expecting this. Hayashi dodges the very large swipe, leaping onto and then kicking off of a nearby tree to go over the tail(s?) and landing on the other side of the swipe.

"That's terrible!" she says, laughing.

Hmmm. Let's do setup for later, while they're waiting for Fushiguro. She starts sending out needles into the environment, eye side embedded into the scenery, pointy side out. In places Itadori is unlikely to be thrown into or land on accidentally. Accidentally stabbing her partner (heh) would not help anything. This will maybe become relevant at some point! Or not, she'll find out.

Yeah nah, it was expecting her too and as soon as she and Itadori dodge its swipe it immediately swipes in the opposite direction to try to get them where they stand.

It definitely gets Itadori, who for the second time today gets launched against a tree.

It does not get Hayashi, but it does come close. She hisses a swear word and decides that maybe she should focus more on the present instead of setup for the future. Anyway, it seems like Itadori is probably going to get tossed around a bit, best to keep the environmental hazards to a minimum.

He's hardy, at least, and recovers quickly. Here's another swing at the gigantic crocodile—

—who dives into the definitely-not-deep-enough-to-hold-it swamp water, and disappears from their senses.

"Hate domains, hate them so much," she grumbles. "Mind the water, I think it needs it to travel!"

Well he can jump onto a tree like a monkey, just in time to avoid the emerging creature with its maws open wide enough to reach both of them.

...it's an opportunity, in his opinion, and he drops into the creature's mouth.

"What kind of dumbass move was that?!"

She dodges. Again. It's rather a theme. And then she throws some needles at some of its many eyes, because maybe they'll hurt it enough that it'll get distracted. Which is important, so that Itadori can do whatever stupid, insane move he seems to have planned, the lunatic.

The creature shuts its mouth and tries to swipe at her yet again—wait, no, it's thrashing? It's moving erratically, and soon enough one Itadori Tōkan, covered in slime and goo, cuts his way out of the side of the curse's neck (helped by his superstrength, it really is unreasonable how strong this boy is), and says, "Catch!" before throwing something in Hayashi's direction.

It's a tongue, enormous and twitching in the air.

The curse is having none of that. It decides to go all-in against Hayashi and stop her from grabbing its body part even if that means hurting itself. It has an idea of what she'll do with it and it really, really doesn't—

—and hold that thought because now there's another giant snake on the field? Except it's not a curse, it's white with a long black stripe along its back and Fushiguro is coming with it and directing it to straightforwardly wrestle with the crocodile.

Okay, insane plan seems to have worked, whatever! Hayashi has an opening and a job to do so best to get to doing it.

She throws needles towards the tongue as it flies to her, then leaps after them with as much speed as she can manage. Her fan (and needles) are pointed at the proper angle to impale the tongue, everything is given as much momentum as she can manage, and she summons up a whole hell of a lot of cursed energy in all of them. All at once. Big finishing move, go.

It works.

The sympathy between the tongue and the creature plus the amplification of her cursed technique make a myriad enormous needle holes appear on the crocodile's body. Fushiguro dispels his snake lest it get hurt by it, and watches as the crocodile writhes and dies, screeching the painful noise curses make.

As it dissipates, so does its domain, and they find themselves standing in the middle of the construction site again, no goo or swamp water visible anywhere.

"Our third arrived just in time for the climax!"

"...your what?"

The innuendo startles a laugh out of her, and then wait no it is serious time.

"Don't worry about it," she assures Fushiguro, the precious socially anxious cinnamon roll, "and you—"

She points at Itadori, "—are a lunatic, I know it worked but jumping into its mouth, what kind of insane plan was that?!"