[Author's note:This is a one-off, and is NOT part of the same continuity as the Resilience series. Warning: character deaths.]
Bruce had always figured either he or Thor would be the last. The smart money said Romanoff and Barton first, then Stark, then Rogers (who though apparently immune to aging was not invulnerable), and then the two immortals, or near-immortals.
As it turned out, though, Tony went first. The astrogliocytoma was incredibly aggressive, too spread out for surgery, and resistant to both chemo and radiation. It gave him enough time to make a will. Jarvis fell silent at the same time as the heart monitor. No one knew whether he'd deleted himself, or taken advantage of the upgrade Tony had installed to upload himself to the cloud.
Bruce had been there to support Pepper in her grief, and as she began to recover he was still there.
They married on the fifth anniversary of Tony's death.
Hawkeye was the next to go. He was cleaning his gun when he first noticed the tremor in his right hand. Later, he took that as an omen. As the Parkinson's progressed, his quiet voice got quieter, his impassive face more impassive.
The night before he left for Yosemite, he spent with Natasha. She guessed what he was planning, and she made the night as memorable as she could, for both their sakes.
The next day he climbed El Capitan, wrote a note of apology to the recovery team that would be sent after his body, and leaped from the top. He left his bow and arrows to Natasha, and the rest of his estate to the park's search and rescue fund.
Bruce and Pepper had twelve good years together before the aortic aneurysm they'd both known was lurking inside her finally dissected during a bout of coughing from a routine cold. She died in his arms, with merciful speed.
Shortly thereafter, Erik Selvig died peacefully in his sleep.
Steve was leading an assault on a group of domestic terrorists when they decided to blow themselves up, and him with them. Flags flew at half-mast for three months.
Jane Foster, in the peak years of her career, was coming down from Cerro Tololo when her car blew a tire and swerved out of control. She died of massive head injuries, before the fire started. Thor attended her funeral, then bade the rest of his companions farewell and returned home.
That left Bruce and, surprisingly, Natasha.
She retired from field work after Clint's death, but continued to serve SHIELD as an analyst and trainer for eighteen more years, until her stroke. Then she moved into the retirement home that the Stark Foundation administered for SHIELD personnel. She consulted with historians occasionally, if they took her fancy, but she steadfastly refused either to grant interviews or to write her memoirs.
Bruce, in all that time, had barely aged. His hair was touched with grey at the temples and he was a trifle slower and quieter. It had been decades since the Hulk had come out to play without being invited, and years since he'd been needed at all. Better-controlled, better-understood techniques of physical enhancement had made him obsolete. He continued his research, and as a hobby would return to med school every decade or so to train in a new specialty. He was offered guest lectureships, which he sometimes accepted, and faculty positions, which he turned down.
He visited Natasha often. He offered his medical opinion if asked, but mainly he just kept her company. She was still a striking woman, her hair still thick but now pure white, falling to her waist when he brushed it for her, though ordinarily she kept it in a neat bun. Her blue eyes were paler now, the arcus senilis clearly visible around the irises, but still fierce and mercilessly observant. She reminded him of one of those ancient ballet teachers at the Kirov or the Bolshoi: tiny, delicate, autocratic, with a sense of humor wielded like a scalpel.
He was with her the day the young spy slipped into her room.
The boy was tall, lean, with intense dark eyes, heavy black hair and beautifully sculptured Slavic cheekbones. Natasha smiled at the sight of him. "Can I help you?" she asked.
He stammered, "Ma'am—I just—I wanted to meet you."
She raised a sarcastic eyebrow. "And who is it you think you're meeting?"
"Chyornaya Vdova," he blurted out.
She grinned. "And how did you find me, Malinki?"
The boy nodded at Bruce. "I followed him."
"Not bad. The simplest tactic is sometimes the best," she said judiciously.
Bruce moved to intercept the intruder, but Natasha held up her left hand—the only one that worked—to stop him.
"Let the boy stay," she said. "I've got nothing else on my schedule. Go do your rounds or whatever; I'll see you at dinnertime."
"All right," said Bruce. He nodded to the boy and courteously pulled a chair up for him.
When he returned several hours later, she was still in her wheelchair, turned to the window, but her eyes were closed. There was a faint smile on her face. She wasn't breathing. A bottle of vodka and a shot glass were beside her, alongside an empty prescription bottle that had held six doses of beta blockers.
She'd left him a note, in her lefthanded scrawl.
Bruce: thank you for everything.
Leave the boy alone; he just brought an old woman the drink she asked for.
Time for us both to move on.
Much to her surprise, Natasha opened her eyes and took a deep breath. She looked around. This was not the sunny, elegant room she'd fallen asleep in.
The black iron gates were inconceivably huge, impossibly old, and wrecked. They were bent, twisted and shattered, and hung halfway off their hinges. The inscription above them, mostly obliterated, now read only ...hope...enter...
Bat-winged shapes swirled above. Screams, flames and explosions filled the air. Judging by the sound of it, most of the action was downslope and to the left.
Of course, she thought. Even the Son of God needs ground troops.
She checked her weapons. Widow's Bite fully charged, both pistols loaded with full clips, spare clips in easy reach, two blades and various useful gadgets ready to hand. She gloried in the smooth, easy movement of her body, the sure dexterity of both hands, the supple response of her legs as she ran, dodging falling masonry, skirting piles of rubble.
She ran toward the thick of battle, scanning the parapets for her partner. He'd be up high somewhere, calling out patterns and strays.