A/N: Welcome to my first story. This is an idea I've had going around in my head for awhile now. It's a V-tamers/adventure crossover...sort of. Anyway write a review, let me know what you think, constructive criticism is always welcome. Please enjoy.

Disclaimer: I don't own digimon.

The Teacher of All Things

Prologue

Tai looked both ways and walked across the road at a slow and steady pace. Mingling with the crowds; he trudged along back to his families apartment; his arms laden with groceries that his mother had forgotten to buy and had sent him to quickly purchase for dinner. The sky was overcast; the dull grey of the clouds blending in perfectly with that of the buildings. The sun beginning to set only evidenced by the darkening skies casting the city into an ever so slight blue hue. As Tai looked at the sky he was unable to stop his mind from wondering, as it did almost everyday, back to the fate of his dearest friend and companion.

About six months ago Tai had entered the D-1 Grand Prix Digimon Tamers Convention with hopes of winning the tournament. People had their V-pets, digital creatures they raised battle each other. He had been denied entry as his Digimon (Zero) wasn't a registered digimon and shouldn't have existed. The commissioner had declared it a bug and when Tai pushed the issue called Tai a hacker and threatened to have him kicked out. Afterwards he had duelled with the tournament champion Neo Saiba and drew with him; another thing that was supposed to be impossible.

Tai had sat down feeling dejected but was then been sucked into the Digital World to the continent of Folder, where he had met his Digimon Zeromaru for the first time. There they had helped save the digital world from Daemon an evil digimon who was terrorising the continent as well as trying to unlock the secrets to ascending to the super-ultimate level, a level above even mega digimon. It later transpired that Daemon had chosen Neo, as the strongest tamer, to raise his super-ultimate digimon and Neo ,who was still bitter at having drawn with Tai earlier, accepted.

After months of adventuring, travelling and fighting Tai and Zero managed themselves to reach the Super-Ultimate level, defeat Daemon, reform Neo and save both the Human and the Digital world from Daemons invasion. Tai had said goodbye to all the Digimon he had become friends with including Zero and had had to leave along with the other humans who had been involved in his adventure.

After returning Tai had realised that the several months of adventuring in the digital world had only been a few minutes in his. The next day he and Neo, now friends, had battled one last time as equals and Tai had narrowly won. It had only been a few months after that that Zero's lifespan ran out and the V-pet went dark. Tai had been distraught and in many ways still hadn't recovered from his best friends death.

It just seemed unfair that they had faced so much, defeated every opponent and overcome every challenge only to have been so easily and permanently split apart. Tai slowly climbed the steps towards the floor his home rested on.

'Just look at me' he thought. 'Zero would be ashamed if he knew I was moping like this. He would want me to be happy.' But it was difficult to be happy with his best friend dead.

Tai reached his front door and walked in crying out,

"I'm home!"

"About time" His mother much less loudly replied from the kitchen, it was only a few steps away after all. Tai took his shoes off and walked in. He then turned towards her. Yuuko Yagami was a slender brown-haired woman with a kind face. Her physical appearance only topped by her kind personality. "Did you get the groceries dear?" she asked.

"Of course" said Tai putting the plastic bags he'd been carrying on the counter. "Everything you need for your three bean salad" Tai shuddered. After all his mom maybe a wonderful woman but that didn't mean her cooking was any good or even edible. "And a few other snacks"

"Wonderful" she cried and began to unpack the shopping "Oh and could you check on your sister I don't think she's feeling too well." Tai was unable to ignore the pang of guilt that swept through him when he heard that Kari was ill again but nonetheless he nodded and went to check on her.

He knew it wasn't his fault that Kari had such a weak immune system and often became ill. But he couldn't help feel responsible and that if only he hadn't been so selfish Kari might be fine and not have nearly died when she was younger.

Tai hushed his steps and quietly opened the door to his and Kari's bedroom. He peeked in. The lights were off and only the silhouettes illuminated by the lights from the living room were visible. As Tai squinted he could just about see the shape of his 8-year-old sister in the bottom of the bunk bed they shared.

She seemed peaceful and Tai could see the gentle slope of the covers rise and fall in time with the rhythm of her steady breathing. Upon realising she was asleep Tai began to close the door and back out the room but a soft childlike voice stopped him,

"Taichi?"

He froze and stared as the shape under the covers moved and the heart-shaped face of a small girl appeared lit up by the light.

"How are you feeling Kari?" Kari's face scrunched up as if confused by his question. Then after a few moments she looked up at him,

"I'm feeling fine Tai. Never better. We'll definitely be able to go to summer camp tomorrow" she said. Her bold words were rather ruined however by the creaky voice in which she spoke. Despite her shrunken eyes, obvious parched throat and red face she still managed a smile while she said this.

Tai felt his heartstrings tug at such an obvious lie and that she would still be willing to go just to cheer him up. He couldn't let her torture herself just to make himself happy. She had done that without him knowing before and even now he could still in his darkest moments hear the sound of the siren and people shouting as Kari just lay there so still...

No! Tai shook his head and cleared away the demons of the past. He had vowed that would never happen again. He slowly crossed the small room and sat on her bed. Putting his hand on her forehead and tenderly brushing way strands of her brown hair whilst saying as gently as he could,

"Don't worry Kari, its ok. I'll just look after you while you stay here and recover. Your burning up after all. You don't want your fever to get worse do you?" Kari was visibly more relaxed with his cooler hand on her forehead and she spoke more quietly. Tai was barely able to hear,

"But brother's been so sad lately..." Her eyes began to droop and her breathing began to even out. "I want you to get better..." Kari's eyes closed completely. Tai swallowed and slowly stood up and crept away from the bed towards the door.

Even Kari had noticed how depressed he had become since Zero's death although neither she nor anyone in his family actually knew what had happened. His Mom had become extra nice to him since; whereas his Dad had blamed it on hormones. But only Kari knew of some of his emotional turmoil.

When after the first few days he had cried himself to sleep at night and had had nightmares Kari heard it all. He had asked her to not tell their parents which she had reluctantly agreed to. Perhaps she was still too young to understand his loss but even so she did her best to cheer him up which Tai was grateful for.

Tai shut the door and saw his Mom looking at him from the kitchen expectantly.

"She has a fever, she won't be able to go to summer camp tomorrow" Tai said, answering her unasked question. Yuuko sighed,

"Oh well. I'll have to call the campmaster and tell him you two aren't coming then." She knew Tai wouldn't want to let his little sister out of his sight when she was like this. She had hoped that this summer camp would provide a change of scenery that would perhaps get Tai out the depression that he had been in for the past few months. Neither she nor her husband understood what it was that made him so depressed only that Tai's bad mood had affected the family.

Her son nodded and was about to turn away when what Kari said struck him,

'I want you to get better'. Tai stopped in his tracks wracked with indecision. He didn't want to leave Kari but she would never forgive herself if she thought that she was making him unhappy in any way. 'Maybe it will be good for me. These summer camps have loads of stuff to do after all. It may take my mind off of him...' and that was the crux of the matter. He may regret this later but then again Tai had always been rash and impulsive. Tai swallowed and said to his mother,

"Actually Mom if its ok with you, I would like to go to camp anyway." Then winced at his poor choice of words, "I mean it's not like I don't care!" He clarified stuttering a little in his panic, "I just think that you can take care of her ok by yourself and err.."

"Tai, it's ok" His mother said. He could see her smiling at him. "I'm glad you still want to go to camp. It will be very good for you to do so." She picked up the phone and began to dial. "After all I've heard rumours that a certain friend of yours will also be going" Yuuko said mischievously grinning at him while holding the phone to her ear.

This took Tai by surprise. Someone else he knew was also coming to Summer camp? He didn't know very many people who were particularly active. Well except for his enemies-turned-friends the Alias III and Neo. But then again his mom didn't know about his friendship with them as they went to different schools.

No, the only person Tai knew who would willingly go to summer camp was Sora. But she would have said something if she was going. Right? Tai took a look at his mother's grin and put two and two together.

"Sora's going isn't she" he said knowingly, "And what's with that face?" he continued upon seeing his mothers grin.

"I just think it's interesting that Sora's the first one you think of when I said one of your friends is going" She then wiggled her eyebrows expressively. It took Tai a second to get what she was implying but when he did he went red in the face and yelled,

"It's nothing like that! Sora and I are just friends!" then mumbled, "I didn't even know she was a girl until recently" his mother chuckled clearly hearing him, then began talking into the phone.

Tai sighed and sat down on the sofa, turning on the TV. How was he supposed to have known that Sora was a girl? They had known each other since they were five and she had always played in the same soccer club as him. She had always worn boy clothes and had short hair. They had even fought each other occasionally! He hadn't always won either.

It wasn't until the beginning of the school year, a few years ago, when she had transferred to his school and shown up in his class wearing a skirt. Tai had then cried out, with his usual lack of tact, in front of the whole class

"You're a girl?!"

That set the tone for the rest of her first day at her new school. Sometimes he swears he can still feel the bruises she gave him that day. Although she did later forgive him though and just called it another example of his "knucklehead behaviour". Tai had been too embarrassed at being beaten up by a girl to think of a comeback to that.

"Meanwhile several freak weather occurrences are being reported in throughout the world" This drew Tai out of his thoughts and he sat up straighter. The news reporter continued, "... and America has reported its coldest summer yet with temperatures on average across the whole of the country of less than 10 degrees Celsius. Many areas of Asia are suffering from severe droughts the likes of which haven't been seen since..." Tai tuned out the weatherman, 'I thought I saw something there...' he thought, 'for a second there it looked like a-'

"I've just got off the phone with the campmaster and he's knows yours sisters not going" His mother said. "What are you watching?" Tai sighed and turned off the TV.

"Nothing. I'm going to bed"

"You don't want any dinner?"

"No thanks. I'm not hungry, goodnight." He then began the walk to his room when suddenly the phone rang. Yuuko picked up the phone,

"You want to speak to Tai? Sure he's right here." she gestured him over and gave him the phone, she then went into her bedroom leaving Tai alone in the room.

Tai put his ear to the receiver

"Hello this is Tai speaking" he said.

"Hey Taichi it's Hideto" Tai's eyes widened. Hideto had been a member of Alias III, a group of powerful tamers led by Neo to try to stop Tai and Zero. Hideto was the strongest of the three and his partners had been a Wargreymon and a Metalgarurmon who he could Jogress into Omnimon.

Tai still regarded their fight as one of the toughest he'd ever had. It had only been due to luck and Omnimon's own sense of righteousness that Tai and Zero had won that battle at all. Since that day Tai and Hideto had had ,along with the rest of the Alias III and Neo, a sort of friendship due to their shared adventure.

"What's up Hideto. How have you been?" Tai asked tried to ask nonchalantly,

"Alright. The important thing is how you've been holding up" Tai frowned, 'this again...'

"I've been fine. You don't need to keep checking up on me ya know!"

"Well Neo told us that we should keep tabs on you, call you every once in a while, make sure you don't do something stupid" At that Tai couldn't keep the anger from his expression. Of course Neo would be the one to order them to keep a lookout. Neo had been the one to see just how deep their bond was and what could easily happen if he gave into despair. Tai sometimes still dreamt of that battle against a monster most could only imagine in their deepest nightmares. When he let go of Zero's hand with tears in his eyes, resigned to his fate and just fell...

Tai shook himself awake, away from that dark place and back to the light of his living room. Hideto was still talking,

"Neo said he wanted me to call you tonight since you'll be at camp for the next few weeks and we won't be able to contact you"

"You don't have to watch my every move. I'm not a child" Tai stated to the older boy,

"I know that." Hideto's voice grew softer, more personal, "It's just you just haven't been the same since Zero's death. We can tell, all of us. Even Rei." Tai inwardly winced, "But...you need to be strong. Keep looking forward remember?" Tai found himself growing annoyed at having his own words thrown back at him,

'Of course I'm looking forward I'm still living aren't I?' he thought bitterly.

"Just remember that your partner will want you to be happy ok, I mean that's what..." Suddenly Tai noticed that he could hear Hideto's voice struggle, "I mean that's what Warg and Melga said to me anyway."

'Of course' He remembered with horror his anger draining away, 'He doesn't know what happened to his partners. They wanted to stay in the Digital World instead of return with him. And he... truly cared for them as well.'

That they would leave him like that whereas Zero had chosen to stay with Taichi was what hurt the older boy most of all.

"Just...just don't do anything stupid ok Tai?" Tai nodded, struck by surprise at the strength of his partly repressed emotions, "Just promise ok Tai? I don't think any of us could take it if something happened" Tai nodded again. They didn't need to say out loud what he meant by something or him doing something stupid.

"I promise"

"Good. I'll see you in a few weeks then. Try and enjoy yourself. Goodbye." Hideto finished abruptly,

"Bye" Tai stared at the phone for a few seconds before hanging up. As he did his mother re-entered the room.

"Finished talking with your friends?" she asked,

"Yeah. I'm going to bed. Goodnight Mom" he replied walking into his room and shutting the door behind him leaving his mother looking perplexed at his abrupt departure.

Yuuko sighed. She had hoped to coax a bit more spirit out of him over dinner. She had gotten him to open up a little though and had managed to catch a glimpse of the happy and lively boy that she had raised before he shut himself in again. Yuuko sat down and looked at the ceiling in thought.

'I hope this summer camp helps break him out of this depression. If it doesn't I don't know what else to do.' All attempts at coaxing the reason for his depression out of him had been for nothing. For whatever reason he didn't trust either of his parents with the cause for his grief.

That hurt her more than she cared to admit. He had gotten better however. He smiled more and even joked occasionally but he was still far from the fun-loving boy she remembered.

In his room Tai lay on the top bunk of the bunk-bed emotionally exhausted. He stared at the plain white ceiling his eyes lazily tracking the dancing shadows created by curtains and the pale moonlight. Tai couldn't help but wonder how this summer camp was supposed to help him get over Zero's death. How had the others withstood it? Sigma's Piedmon was killed in front of him by Arkadimon while he stood helpless to interfere. Piedmon had been injured from his battle with Zero and Tai and could barely put up a fight. Tai and Zero had seen hopeless battles before but they had either managed to win in the end somehow or have something else come in and save them.

Tai couldn't imagine how distraught he would be if Zero had died like that in front of him. Mari had also seen her digimon killed in front of her. Rosemon had sacrificed herself to stall Arkadimon so that Hideto and Omnimon could retreat and help defend Lord MagnAngemons castle. Neither of the two had been too upset about it although they had been sad. They both admitted that their relationship with their Digimon had been far more professional and a lot less intimate than Tai and Zeros had been. Sigma had confessed to Tai that he and Piedmon had only just begun to start opening up to one another before he had died.

Tai had tried to help Sigma and Mari get over their grief before Zero had died. Neo, Tai knew, was far more complicated. Neo had originally been as ruthless as can be, deleting his Digimon if they didn't grow as strong as he had expected, and Neo had very high standards. His former partner Metalgreymon had been so loyal to Neo that he had even obeyed Neo's orders to take Zero's attacks head on, even as he was being dissolved into data, he never stopped trying to get Neo to be proud of him.

It had all been in vain as Neo hadn't cared seeing Metalgreymon as just a tool to be used and discarded. To be replaced with a better tool as soon as it was available. It wasn't until the end when Neo was free of Daemon's influence that he showed regret.

Rei had told Tai that sometimes she could hear Neo crying in his room, although there would be no evidence of such if she went in and Tai wouldn't dare ask Neo about of them had had the heart to pick up a V-pet device after their partners had died. It was like losing a part of your soul. It would be unthinkable to see and treat the V-pets as toys after all they had been through. Instead they had all kept theirs in various hide holes around their houses, their screens dark and lifeless.

Tai still had his stuff from their adventure hidden under a loose floorboard under Kari's bunk. If you pried open the floorboard you would find a small metal box which contained two items; his V-pet device and his yellow cloak that he wore across the digital world. Tai would occasionally when he was alone take them out and just stare at them. All their past experiences would flash before his eyes. Their first meeting, collecting the five tags, fighting Neo, digivolving to super-ultimate, their victory dances...

Tai felt his eyes well up with tears. He quickly wiped them away.

'Every night I get like this. When it's just me alone with my thoughts. When it's just me alone in the dark I can't help it! It's not fair! From when I bought that V-pet and his egg hatched I raised him' His sorrow quickly turned to anger,

'Stupid summer camp won't make me forget Zero, I'm only going because Kari would be upset if I didn't' With that justified in his mind Tai closed his eyes and let the soft rhythmic sound of Kari gently breathing in the bottom bunk put his mind at ease, at least for a little while.