"I meant no insult!" Dodge ball of lava. "I don't intend to interfere, you said no!" Dodge house-sized spear of ice. "I'm leaving peacefully, okay, so stop tearing up the tile!"
"You'll respawn at home. No permanent damage. You interrupted an important meeting, you need to learn a lesson about territory, mountain bitch." Dodge- no, fail to dodge a thrown tree, and then another ice ball. The next sphere of magma is what destroyed that form.
She wakes up, stripped of all her tools and enchantments and even clothes, and groans in pain.
She's heard of nuclear power. She knows it could be devastating, but not much more than that. "Mountain here. Can I move the reactor without it exploding?"
"No. Can't transmute things directly. I can... Spread the fuel out, or make shielding if something sufficiently natural counts as shielding."
"I can make all those in sufficient quantity. I can make a heat sink, but it might not be enough."
"Still fighting B. It's busy out here." Another statue 'dies'. She puts a boulder between B and some cape with giant cat ears on their costume, but lightning just curves around it. "Waste of time to fly there unless you think it'll work. Will it?"
She finishes her current task (moving an entire building, including the shelter under it, out of the path of Behemoth's kill radius) then flies for the reactor. The comms system is handy - she doesn't get lost thanks to a computerized voice giving her directions.
She has a medium-size pile of the requested elements in a ball in front of her by the time she gets there. She lands hard in front of the first science-looking person. "Mountain here to help clear the reactor. Clock's ticking, where to?"
"I can already feel them. The rods of stuff producing intense heat, slowly changing into something else, surrounded by water, correct?"
Not the time to quibble over manners. "Okay, and the rods of cadmium and friends-" She waves her ball of alloy "-nearby the fuel, you need more of those?"
"Right. So I give it more moderators, more shielding. If I can cool it down enough too can I pick the whole thing up and send it away from Behemoth?" She is floating briskly towards the reactor buildings during this. Her ball of alloy breaks up into four chunks and starts working its way into the reactors. The control rods extend and bulk up - she asks for advice on how exactly to pattern them and follows it rigidly.
She looks distant for a moment. "...I'm strong enough. Fine control on something as big as this whole complex would be a bit iffy. Still need the cooling though, right?"
She taps her comm device. "Mountain reporting. Reactor is stabilized, but not for long if Behemoth gets here. I can pick up the whole thing and fly away if we get someone to cool the interior well enough. Any tinkers or shakers think they can do it?"
Brief consult with the Science People, then: "If I move this place the coolant pumps will shut off. The reactors keep making heat for a day or two even after they're shut down, just not as much. I just need the reactors to not melt for ten minutes to half an hour while I move the whole building and they start the pumps again. About eighty megawatts' worth of heat right now."
She redesigns her heat sinks, which still doesn't help that much, and puts more shielding over both the reactors and the piles of waste sitting in a big pool in different corner of the building. And she waits.
"This way."
It's a grid of metal fanning out in all directions, a classic heat sink. The parts closer to the reactors are glowing red. "Here it is, tell me if you need to get closer to the center and I'll make a radiation shield. The nuclear people say alarms would be going off if there were dangerous amounts of radiation here, should be safe for now, but we still want to be as fast as possible obviously."