Disclaimer: XXXHOLiC and Card Captor Sakura belong to CLAMP. Star Trek belongs to Paramount.

Author's Note: I wrote this fic for the "Self-Indulgent Fiction Challenge" at LiveJournal. But don't worry! Just because the premise is crazy doesn't mean I didn't put a lot of thought on the execution. ;) It was a lot of fun, trying to figure out how to make this work.

I'm using manga canon for CCS and HOLiC. So, if you find yourself wondering "why didn't he use such and such Card?", remember that he's got only nineteen of them. After all, it's more of a challenge this way...

I

Sometimes, Yuuko's business required diplomacy. A title like Witch of Dimension meant that she had no way of going unnoticed. That, in turn, meant that once in a while she was visited by some of the most powerful entities in the multiverse. The downside was that, as she had soon found out, those tended to be the most annoying ones too.

And, right now, she was stuck playing shogi with who was possibly the most powerful and most annoying of them all.

Q had randomly showed up at her house, as he often did. Her own premonition was the only warning that she had got. Then again, at least he wasn't one of those who assumed people would expect them; quite the contrary, he seemed to enjoy the shock. For a nearly-omnipotent being, his interest in humans was unusual. Most of the powerful aliens out there just ignored them. He messed with them and had a lot of fun in the process.

Luckily, Yuuko was one of the few mortals who had earned his respect – if it was because of her power or her sense of humour, she hadn't found out. In any case, he had never caused her trouble. He simply visited once in a while, dressed in the local fashion even though his preferred human form didn't look Japanese at all, and played games like these while he gossiped about his latest antics.

"Your era is so relaxing," he sighed, moving one of the pieces forward. "People will get insane later, mark my words."

"Later?" she repeated.

"I've just visited a group of really amusing friends in the twenty-fourth century," he explained. Yuuko doubted that those poor people consider Q a friend, but she knew better than to voice her opinion.

"What brings you back here, then?" she asked. "I doubt you came only for a game of shogi."

"Do you think I don't enjoy visiting you?" he told her, pretending to be hurt, but her bored look cut off his teasing at the root. "Of course I have plans. I always do. I come with a lesson on the dangers of having too much pride."

Yuuko made her own move in silence. She knew that there was no need for more questions; Q loved to talk, especially about himself. Indeed, it wasn't long until he started speaking again.

"I mean, you humans can get so cocky sometimes," he said. "You play around in a few worlds and call yourselves powerful. You shouldn't let your ego go to your head so easily."

She looked at him for a moment, considering the situation. She didn't like where the conversation was going. If she knew him well – and she though she did, as well as anyone could know Q, at least – his 'plans' involved playing around with people. That was never a good thing.

"You do know that this is my job, of course," she said slowly. He laughed at her and waved his hand.

"See, there's the ego again. This isn't about you," he told her. "It's your boyfriend who needs to get a bit of perspective."

Yuuko nearly choked on her sake. This was bad, bad news – so bad that she didn't even think of correcting the 'boyfriend' part. She would be the first one to say that Clow was way too smug, of course, but Q's idea of giving people perspective was rather different from hers. And considerably more dangerous.

"Oh, don't fret," he said, "I'm not going to hurt him much."

o O o

Something bad was about to happen. Something really, really bad.

Clow's uneasyness had been growing since that morning. It was a horrible sensation. He was sure that there was trouble ahead, but he couldn't quite discern in what form. That uncertainty was the worst part of it. He could tell that someone, or something, was actively preventing him from seeing the whole picture.

That was enough to worry even someone like him. What kind of power was able to interfere with his Sight? The one behind this could not be of this world...

Then it struck him, an icy feeling of dread – the Guardians. It was about his Guardians. He looked up at them, but it was already late to warn them. He only had time to see, horrified, how they were sealed by an external force... a force that materialized just in time to catch them, in the shape of a smirking, rather unimpressive man.

Clow knew better than to let that harmless appearance fool him, however. The sheer power that now filled the room was overwhelming. And, from all the near omnipotent beings that he had ever heard about, there was only one who would waste time bothering simple humans.

"You are... "

"You may call me Q," the stranger said. "But I see you've heard about me. I bet your girlfriend has been talking about me behind my back again."

"Who?"

"Yuuko, of course. How many girlfriends do you have?"

"She's not my –"

"Oh, come on. This isn't the time for denial," Q interrupted, looking almost curiously at the sealed forms of the Guardians and moving them around to see them from all angles. "You, my friend, are in a very tight spot right now."

"I can tell," said Clow. "Give them back."

"Do you really think you're in a position to talk to me like that?"

"Leave them out of this," he insisted. "Whatever is your problem with me, they have nothing to do with it."

"They do, in a way," said the alien. "That's quite an ego you've got there, to go around creating life... But I won't harm them," he pointed out, before Clow could intervene. "I'll just keep them sealed until we come to an understanding."

The wizard bit back an angry reply. It wouldn't do to upset him, after all; and he also knew that he shouldn't try to recover his Guardians using force. It would be pointless to waste his magic like that. Not even his powers were a match for Q – not by far.

"All right. Just tell me what you want," he sighed, running a hand through his hair.

"It's simple, really. We're going to play a little game," the alien told him, with an innocent air that didn't fool anyone. Clow gave him a long look, suspicious of his attitude. This certainly couldn't end well.

"What kind of game?" he asked at last, frowning.

"My favourite kind," said Q. "One where I set all the rules."

"But what am I supposed to do?" the wizard demanded, between confused and exasperated.

"Oh, you'll find out. Hopefully."

"That hardly sounds fair," Clow muttered.

"Too bad," was the nonchalant reply. "Now, rules. First: I keep these until you win. If you win, that is. Second: you get to keep those Cards of yours, because you'll need them. Third: no outside help unless I feel like it, so don't bother trying to contact anyone."

"When does it end?" he asked.

"When you find out what you have to do and do it. Or when you get killed. Whichever comes first."

"Well, isn't that reassuring..."

"And the most important rule of all," said Q, "no peeking ahead!"

Clow winced. He could feel a good deal of his power slipping away from him, draining, and he couldn't tell if the sensation had lasted forever or just a second. He felt light-headed when it was over, as if he was too empty. Something was missing...

When he opened his eyes, he was alone. That wasn't a problem. The problem was that he was in the middle of a jungle. Instinctively, he took his hand to the pocket where he kept his Cards, and sighed in relief when he realized that they were still there. At least in that respect, Q had kept his word.

He looked around, trying to figure out what to do. The jungle was thick, so much that it wouldn't make sense to use Fly. There was only a narrow path that he could follow. It seemed that walking was his only choice.

Without really noticing it, he clutched the Cards in his hand. Knowing that they were there was his only comfort in that situation. He was alone, lost, and still dizzy.

And he had no idea of what would happen next.

o O o

"That was cruel," Yuuko said.

Q didn't seem to mind it, nor her constant pacing around the room. He had made himself comfortable on her couch – without invitation, of course – and was throwing a Magic 8-Ball up and down.

"How so? He didn't enjoy these, and I took them away." The ball fell onto his hand yet again as he finished speaking.

"Will you stop playing with that?" she snapped, before quite realising who she was talking to. As much as she hated to admit it, it was a good thing that Q found her moderately amusing. It was the only reason why she could get away with shouting at him like that.

"I'm not going to break it," he said. "Not that I think your friend would mind."

"See, that's exactly what I'm talking about," she sighed.

"You humans are never content," he replied dramatically. "I grant him his wish and you call me cruel."

"It's how," Yuuko insisted, still pacing. "You took his Sight now that he needs it, but then what? The moment he could start to enjoy it, he'll get it all back. And he's not an idiot, Q. He knows that."

"That's part of the test, too."

"You're just laughing at him," she muttered.

"Of course. That's what it's all about," said Q. "There's no need to get all sentimental about it, you know. At this rate, you'll end up asking me to let you go help him."

Yuuko snorted. She knew him too well to play along with his tricks, and he obviously could tell that. He wasn't even trying.

"Because that would change something, right?"

"I don't know," he replied. "Let's ask our oracle, shall we?"

The window on the 8-Ball read Don't count on it.