Prompt: Since everyone knew that the White Stag would give you wishes if you caught him, there must have been previous chases. What did at least one Narnian plan on wishing for?
"There was a White Stag," Tumnus said, "who would give you wishes if you could catch him. There were many, many hunting parties pursuing the Stag." He smiled softly as he remembered those joyful times. "But he has not been seen in Narnia since this winter began."
Lucy sat silently for a moment. "What did you wish for?" she asked finally.
Tumnus' hands stilled as he poured himself another cup of tea. He had not been expecting that question. "I never caught the stag," he said at last.
"Well, what would you wish for if you did?" Lucy persisted.
"I…I don't exactly know," he managed. That wasn't true though. He knew exactly what he would wish for. Then, and now. Back then he was a silly faun, wanting only more friends or a nicer pipe, but now… now he would wish for his father back.
A lump rose in his throat as he thought of his father the last time he'd seen him, going off, hopeful that this time they would overthrow the Witch. His brave, heroic father. He never saw him again.
It was not long after his death that the Witch persuaded Tumnus to work for her, keeping a look out for humans and, if he found any, to bring them to her. Just like he was doing now.
A single thought manifested itself above the rest. My father would never do something like this, kidnapping an innocent girl. He would resist.
This doesn't exactly show a chase and maybe that was the whole point of the prompt, so I hope this works!