Starkiller walked towards Vader. He raised his saber, and brought it down- next to Vader, instead of slicing him in half.
He turned to Palpatine. "I'd love to," he said, "but I think I'll take care of two problems." He hoisted Vader in the air again, then blasted him with lightning. WIth his other hand, he pulled Juno towards him, but not too roughly. He then launched the electrified Vader at Palpatine. When Vader hit, the lightning inside him released in a grenade-like blast.
He set down Juno, lightly, next to him. "The dark side just got lightened up a bit," he quipped.