Rian's not nearly as good a sensor as Mariko, but her unique chakra's kind of hard to miss at this distance (and Mariko doesn't quite talk like that) - 

She flings a kunai as fast as she can, only for her opponent to dodge. 

Sakura protests, but - "That's not Mariko."

The interloper drops their transformation to reveal the Grass genin from earlier - the same one Mariko had said to avoid. "Clever. How did you know, Rian?"

"Talent," she says, activating her sharingan and already flashing through the handseals for the summoning technique, but - 

Blood spraying from beside her, Sakura screaming, red sky and black clouds - 

Rian falls to her knees, gasping for breath, shaking. She takes a deep breath, nearly retches, glances over - 

Sakura is frozen and shaking.

"Heh. You can no longer move. Now, let's begin the battle for our scrolls, with our lives on the line - " And he idly throws a brace of kunai at Sakura, as if she's barely even worth the effort it'd take to kill her.

"Fuck you," Rian shouts, moving faster than she ever has to grab her teammate and drag her away. Her fear's already turned to anger, fueling an itching in her eyes. 

"Sakura, get up, we need to fight or run - "

"What - what was that - " she stutters, but shakily follows Rian's directions - only to spot a snake slowly lowering itself beside them.

"Rian - watch out!"

Rian throws herself away from the snake and Sakura - it follows her, good - she finishes the summoning technique, pulling Sen through, only to have to dodge away from her cat. Sen adapts immediately, shooting a fireball at the snake, and while it's distracted Rian darts over and above it, sinking her sword into its eye, then dodging back as its skin cracks and splits.

Their opponent emerges. "Heh. You don't stink of fear like you should, little girl... Prey should try and run away, rather than futilely struggling to fight a predator." And he lunges up the tree, slithering around it like a snake - 

Only to have to dodge as several chakra chains thunk into the bark, bringing him up short.

"Hey, snake freak! Leave my teammates alone!" Mariko shouts, giving Sen an opening to breathe a line of fire at their opponent - who simply weathers the attack with a smirk.

"Good to see you, Mariko."

"Heh. You sure have spirit, little Uzumaki. But - " And he pulls back his sleeve, swiping blood down the seal there, summoning a truly enormous snake beneath him - "I'm afraid I'll have to kill you and take your scroll."

Shit she doesn't have summons anywhere near that size, let alone the chakra for them - 

Well, nothing for it but to improvise. She trades a glance with Mariko.

Who launches herself at the snake - which swats her aside with its tail, then lunges to swallow her.

...Ah, might as well...

She rights herself just in time for the snake's jaws to close around her body, waits a moment, then bursts her chakra chains around her, pulling on her deepest reserves of chakra, slicing the snake's insides into ribbons, then using another chain to catch herself as she falls free, pulling herself up to the branch next to Rian.

Her whisker marks might be thickening slightly. This guy's emotions make it clear he's toying with them, and that pisses her off.

Gross, but effective.

She launches into a shurikenjutsu assault against the Grass-nin, using Sen's occasional fireball as cover for her attacks. Mariko helps, chakra chains and unerring accuracy helping drive their opponent right where they want him - and Rian breathes out fire that shapes itself into a roaring white-hot dragon.

- Which barely phases their enemy. 

"Your eyes are truly something," he says, walking clear of the smoke. His face looks cracked, and they can now see a single golden eye. "But not good enough to defeat me."

His neck elongates, head surging forwards, and Rian can't dodge in time as his fangs sink into her neck.

He's going to get a chakra chain through his neck if she has anything to say about it - 

And he swats her into a tree, hard enough to crack the bark, and she slumps, falling unconscious to the ground below with a small crash.

"My name is Orochimaru. You will be seeking me out for power, Uchiha Rian," he says, and melts into the shadows.

"Fuck you fuck you fuck you," Rian gasps out before her protests fade into screams as the pain mounts. Mercifully, she passes out.

That snaps Sakura out of her terrified daze.

...Okay. Deep breath. She needs to find shelter, needs to get her team safe, how the hell is she supposed to drag both of them - 

(She gets them as far away from the battle as she can, then stashes them beneath an uplifted tree root and sets to making traps. She's strongly starting to regret agreeing to these exams.)

Mariko wakes quickly enough, accelerated healing taking care of her fractured bones. She's still incredibly sore, but - 

She confirms with Sakura what happened, glances at Rian - nearly recoils at the vicious energy roiling off that mark.

Stop. Think. It must be some kind of seal... 

"If you can keep watch, I can keep an eye on this seal, how it's forming might be critical information to removing it," she says softly to Sakura, who nods.

(And when they're attacked, Mariko's eyes flash red - how dare these genin try to take away her teammate - and, well. She's never claimed to be nice, and her red-tinged chakra forms into spiked chains, and Sakura lunges forward with kunai while the three are distracted - )

And Rian stands, gasping, vile chakra racing through her veins - 

She grits her teeth and looks out at the battle, glaring at their bloodied opponents. "Leave. Now," she manages, trying to fight back the rage demanding she dismember them, make them pay for even thinking about hurting her loved ones - 

They do, leaving their scroll behind.

Earth.

Rian half turns. 

"Mariko, do you still have our scroll?"

She nods. "Yeah - you - " That power is somehow worse than sensing Elieyha, because it's her teammate. "Please - calm down."

"Right." Rian takes a breath, another, and - the sheer urge to kill fades. She shudders when it does, stumbling.

"I - "

Right. People who showed up to help Sakura are here. Not the time for melodrama, Rian.

She turns woodenly. "Thank you for the help."

Team Ten nod, and Rian stumbles over to help Ino tend to Lee, until his team arrives to fetch him.

Once they've all gone their separate ways, Rian takes a shuddering breath and turns to her team. 

"So. Straight for the Tower?" 

Nods. "Yeah. Assuming that Orochimaru doesn't come back, I can keep us away from - everyone." Then, quietly - "Rian... I don't think you should be using chakra. That seal... It's got this vile chakra in it, that's trying to spread like poison."