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The Darth Vader theme tune suddenly bleeps from the underbelly of a Ukrainian drone as a marine attaches a mortar round to it before launching the aircraft against a Russian position.
The Ukrainians say their enemy fears this kind of rotary drone in particular because of the size of the bombs it can drop.
Unmanned aircraft used by both sides have transformed the battlefield in the nearly three years since Russia launched its full-scale war.
But another transformation is also looming as Donald Trump prepares to return to the White House.
The president-elect has promised to end the fighting - though without saying how.
Offering a sense of the mood on the ground, several Ukrainian troops told Sky News they were strongly against any kind of brokered deal that gifts land to Moscow.
"I hope the outcome of this war will be just," said Major Vladyslav Tovstii, 28, commander of the Korsar battalion, 38th Separate Marine Brigade, speaking at a drone command centre in eastern Ukraine where his marines call in and track strikes on Russian targets.
"For me, a just peace is the return of our territory. That's the only understanding I have; there's no other way."
Battle-hardened despite his young age, Vladyslav has been fighting since before Russia launched its all-out invasion on 24 February 2022.
Standing in front of a wall of screens, showing video feeds from surveillance aircraft and attack drones, the commander gave his view on the possibility of some sort of compromise deal with Vladimir Putin - something that Mr Trump may well attempt to achieve.
"It would mean that justice in the world is not as I see it," Major Tovstii said.
"A compromise is no longer about justice; it's about concessions, which means that if you are stronger, you can take what you want."
His brigade is among the units attempting to stop a grinding Russian advance towards the frontline city of Pokrovsk.
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The use of drones is a key way for Ukraine to compensate for a lack of manpower compared to the number of soldiers Russia is sacrificing daily for every inch of captured land.
But Russian forces also operate large numbers of unmanned aircraft, with each side constantly adapting their machines to be able to fly further and carry larger payloads.
Another evolution is in the area of electronic warfare, which is designed to jam the signals of enemy drones and force them out of the sky. Countering this threat is critical.
Sky News was given exclusive access to a makeshift Ukrainian drone factory where engineers and other specialists from the marine brigade adapt aircraft to give them a better chance of defeating Russian jamming efforts and flying deeper into Russian-held territory.
"If you don't want to sacrifice your men, your soldiers, you better make this fight distant, right?" said a technician at the factory, who went by the name "Cartman" from the cartoon series South Park.
He said the success rate for his unit's drones is slightly above 50%, but even that level is getting harder to sustain as Russia improves its electronic warfare tactics.
Armed with tools and hunched over drone parts, the team here is working as hard as ever despite growing uncertainty about the future of the war.
"This is such a waste of time, of my time," said Cartman, who volunteered to join the military last year, giving up a senior job at an international company. He spoke in English.
"While some people are creating technologies to save life and to make life better, we are working on technologies - not just to kill the enemy, but to destroy him completely.
"This is out of (contrary to) common sense, but we have no choice. There's no way out. We have to win this war."
Asked what his message was for Mr Trump, Cartman said: "You cannot make friends with a shark attacking you. You cannot talk common sense if the animal wants to kill you.
"What negotiation skills will you apply if you have just to fight for your survival?"
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Back with the marine who had The Imperial March from Star Wars bleeping out of his drone, the attack operation is under way.
The serviceman raced with a colleague to an underground shelter after attaching the mortar round to the drone, which is called "Perun".
It is dangerous to spend too much time outside because Russian eyes are also in the sky.
After the aircraft took off, they tracked its progress on a screen which showed live footage from a video camera also fixed to the machine.
Once over a Russian position close to Pokrovsk - where the heaviest fighting is taking place - the explosive was dropped. The team confirmed a hit.
Oscar, a company commander in charge of this unit, said he had two views on the possibility of a deal that meant Russia held on to some Ukrainian land and the conflict was frozen.
On the one hand, the 22-year-old said it would be good if it meant no more Ukrainians dying.
But on the other hand, speaking in broken English, he said: "If we froze this war, it gives our enemy time for preparing [the] next attack. And this is so bad because we don't have many people."
Asked how he felt about the prospect of a frozen war, Oscar said he would be sad "because my many friends dying... I lost... men of my family... For what? For what [were they] dying?"
Additional reporting by Azad Safarov, Ukraine producer
English (US) ·