"Tails!" Steve smiled. "What's it for?"
Tony grinned and leaned forward. "You'll see," he said and stole a kiss. "Happy New Year, Steve."
"All right, JARVIS," Tony said as he clambered down the stairs to the workshop, leaving a flabbergasted Steve behind amongst the guests, "engage program Luthor-alpha-five-oh-oh-seven, over ride beta-tango-two-eight-three-roger-dingo. Start transferring stuff back to Malibu ASAP."
"Are you certain this is wise?" JARVIS fretted.
"Nope." Tony shrugged. "But the coin came up tails, so I'm gonna get my Lex Luthor on this year."
Six months later
"Tony, please!" Steve pleaded from where he was chained. "Why are you doing this?"
Tony looked up from carefully breaking Clint's fingers. "Because that's how the coin fell this year, Cap."
"I don't understand!"
Tony snapped the second pinkie. "I'd be surprised if you did," he said over Clint's pained, gusty gasps. He stood and looked at the rest of his former teammates. It was probably best to kill them, his emotional attachments aside. It was simpler that way, and it's not like he really had to worry about neat disposal of the bodies. The ocean was right outside.
"But you kissed me!"
"Uh huh," Tony agreed, standing up. "I did. The New Year's kiss is traditional. Didn't want you to be lonely in the coming year." Lasers were quickest, he decided. He dragged the still unconscious Natasha to a handy grate out of the others' line of sight and sliced off her head before methodically working his way through the others.
Steve he saved for last.
"I can't believe you!" he cried, tears streaming down his face.
"That's not really my concern," Tony said, yanking hard when Steve's chains caught in the grate.
"Bruce is coming - he'll get you!" Steve was crying in earnest now.
"I'm fully aware he's the cavalry," Tony said. He'd had a plan to deal with the Hulk for months now, just waiting to be put in action. "You should probably not struggle, Steve," he said, attempting to arrange Steve's body to his liking. "Unless you want a messy death, anyway." Tony powered up his laser again and went to work.