“Grenades! Grenades!” Perun screamed. “More! ”

They needed to hit the cellar entrance. Kyivstar’s companion had left him behind and was walking there alone. His call sign was Wolf. He was a welder from a rural village in western Ukraine who, when the war started, had been working in the Czech Republic, sending money home to his wife and their young son and daughter. He’d been with 1st Battalion for about a month, and this was his first mission. Sever hadn’t intended to bring him to Tabaivka, but Wolf was filling in for the soldier who’d broken his leg when their truck crashed into the crater. At the house, Wolf had struck me as the team’s most timid member, sheepishly observing Sanjek and Noah’s shenanigans. When the stormers were leaving for the operation, Banker had scolded Wolf for guzzling a tall can of energy drink, which would make him have to urinate. In the cargo van, right before Banker shut the door, Wolf had said, “Fuck, I forgot my ballistic glasses. Oh, well, whatever.”

He was now doing something inexplicable. Instead of sneaking up to the cellar entrance, he was approaching it openly—revealing himself to anyone who might be watching from inside. “He was confused,” Kyivstar later told me. “I was yelling at him, trying to get him to come back.” He added, with frustration, “There was no need for him to go ahead by himself like that. It was like he was going there to die.”

In the operations center, Perun yelled into the radio, “No! Don’t cross in front of the entrance!” But Wolf couldn’t hear him. He kept walking until he reached the open door. For several long seconds, everyone in the operations center watched as he stood there, motionless. Then he crumpled.

“They got him,” Perun said, not loudly, and not over the radio.

He tried to reach Sever. When there was no response, he contacted the repeater on the ridge. “Repeat everything I say,” he told him. “ ‘Climb on top of the fucking thing and throw grenades in from above.’ ”

The stormers, however, knew something that Perun did not. Wolf had frozen because he’d been surprised to see, instead of a staircase descending straight into the cellar, a room a couple of yards long and then a second door, which was closed. The staircase was behind that. Wolf had been peering into the room when someone behind the second door shot him.

Kyivstar and Banker backed away from the entrance. Casper, the sergeant responsible for training the anchor group, was in the operations center that morning. Bending close to the monitor, he said of Wolf, “It looks like he’s wounded.”

“Then why isn’t he crawling?”

“I can’t watch this,” Casper said. He turned to leave the operations center but stopped midway. Dark splashes were bursting in the white yard, around the entrance, where Wolf lay.

Perun said, “The fuckers are throwing grenades from inside!”

Meanwhile, someone from across the three-hundred-yard gap was firing on the team. Bigger, darker splashes appeared much closer to Kyivstar and Banker. “A.G.S.,” Perun said, using the abbreviation for a Russian automatic grenade launcher. “Son of a bitch!”

He ordered the stormers to retreat, and asked Sever whether Wolf showed any signs of life. If he was still alive, they would be unable to shell the area.

“Sever can’t say for sure,” the repeater replied.

Boyko zoomed in on the body, which appeared to be lying in a fetal position. “Group decision,” Perun said to his staff. “What is his status? Casper?”

“He’s dead.”

“There’s no movement,” another soldier said.

The remaining stormers fled the property as more A.G.S. rounds exploded in it. Perun told them to get away and find cover. He needed to think about what to do next.

For the rest of the day, a steady stream of small groups of Russian infantrymen—between two and six soldiers each—walked to Tabaivka from the east. Few made it across the three-hundred-yard gap. The snow had relented, and Boyko easily stalked the groups with the surveillance drone. Perun bounded between the panel and the radio, shouting himself hoarse, calculating azimuths, and correcting the aim of his stormers, snipers, and machine gunners. It was madness: Russians kept marching down the same paths, to the same spots where their comrades had just died. One 1st Battalion machine gunner later told me he had fired his weapon so much that it had kept him warm in his frigid dugout. He couldn’t see the men he was killing. But since they kept reappearing in certain places, he memorized different branches below which he could point his barrel to hit specific coördinates up to a mile away.

Unlike the machine gunner, those of us in the operations center had a bird’s-eye view of the Russians on the receiving end of the barrages: men running and stumbling as they fled the bullets and the shells, crawling after being shot or hit by shrapnel, hiding behind tree trunks and under bushes. At one point, the monitor displayed six Russians hurrying up a road toward the safety of a dense forest. Two of them were helping along a limping soldier who had his arms draped over their shoulders; two others were dragging an injured or dead soldier across the snow on an improvised toboggan. Perun called in cluster munitions on them: a smoking warhead that scudded down, followed by a dozen impacts all around the group. Another 1st Battalion drone pilot was attacking Russians with F.P.V.s. Footage from one of them captured two infantrymen diving away, too late, in the split second before the F.P.V. detonated and its video feed cut out.

Above the monitor that showed this procession of carnage hung the flag with the angel of death playing his flute. I recalled the “joy” that Perun had mentioned. (During other conversations, he’d referred to the “aesthetic pleasure” of his work.) The Ukrainians in the basement derived obvious satisfaction from the Russian casualties, some of which elicited rapturous cheers. “Oh, look at them run!” Perun exclaimed, almost giddily, after one strike.

When night fell, Boyko switched on a thermal camera, and the black figures dying in the white snow became white figures on black. Sever and his team rotated out from Tabaivka at 2 a.m., while the Russians were preoccupied with their hopeless efforts to reach their marooned comrades in the root cellar. The stormers had been walking and digging and fighting for forty-eight hours.

I noticed that he was wearing a pair of rubber slippers with “WOLF” written across each strap. They were his dead subordinate’s slippers. When I asked how the team was feeling about the loss, Sever said, “Like shit, but it’s not the first time. We know tomorrow it could be us.” He planned to call Wolf’s wife. She would receive an official notification, but, until they recovered the body, Wolf would be classified as missing in action, and Sever wanted her to know the truth.

One by one, the rest of the team joined us. Banker moved stiffly, from lingering muscle cramps, and Sanjek’s hands were swollen. He and Noah began grinding up a slab of beef for meatballs. In the afternoon, Casper made them all review the video of the assault on the root cellar. Nobody spoke as they watched Wolf collapse in front of the door. They didn’t know why he’d acted so recklessly. “Maybe he wanted to do something courageous,” Sanjek speculated.

During the next five days, the Vampire unleashed a deluge of heavy ordnance on the root cellar, including twenty-pound thermobaric bombs. But the subterranean structure held. According to intercepts, some of the Russians inside were badly injured, and they were out of food. Their unit continued to send reinforcements, who continued to be killed. Three more Russians were taken prisoner. Now and then, one of the men in the cellar would make a run for it. Each was mowed down. When a 1st Battalion sniper shot and wounded a Russian near the entrance, Litsey—whom Perun had left in charge of the operations center while he rested—ordered the sniper not to finish him. He wanted the Russians in the cellar to hear the soldier dying slowly and pleading for help. During a siege, Litsey told me, “it’s important to lower their morale.”

The temperature warmed and the snow melted. The world on the monitor was transfigured from a blank expanse to a colorful and variegated landscape teeming with detail. The room above the cellar had been razed, and the second door had been shattered; the Russians below had hung up sheets to prevent the Ukrainian drones from seeing down the stairs. Wolf’s body lay amid the rubble. One afternoon, Boyko came by Perun’s apartment to collect leaflets that Perun wanted him to drop around the entrance. The text on the leaflets guaranteed the safety of the Russians if they surrendered. “We invite you to exercise common sense,” it said. “There is no need for you to die in a foreign country for someone else’s interests.” That night, several of the Russians, in a desperate dash, successfully escaped. Those who remained in the cellar were presumed to be too gravely wounded to pose a threat.