A.N. Making up for that short chapter…Here's a longer one! And the next should be soon

The usual was an unused classroom on the fourth floor. It was rather small and poky with a nasty draught sweeping through the ill-fitting window. There had been a couple of desks and chairs stored in the room, Sherlock and John had unstacked them and now they were standing in the centre of the room forming one long table. The chilly room already looked like a secret laboratory; two cauldrons were perched on the desks, various potion ingredients and utensils were scattered about the room, and numerous textbooks, notebooks and rolls of parchment littered every available surface.

Sherlock had gone straight to the classroom after the Great Hall. He was now sitting leaned back in a chair with his crossed ankles resting upon the table. Hands pressed together under his chin with his eyes closed, it looked as if he was praying. The grey eyes opened to the sound of wood brushing across stone flags; John slipped into the room and shut the door quietly.

'It was hard to get out! Apparently we're not allowed out of the common rooms after six now.' He informed Sherlock.

'Hmm. Good thing we're experienced at sneaking about then.' He grinned. John raised his eyebrows at him, the Ravenclaw was obviously in a good mood, and it didn't take a genius to know why.

'So. Got any ideas?'

Sherlock sighed. 'There's not really much to go on. And there's no chance of getting a look at where it happened seeing as the teachers have tidied up and didn't even mention where it happened.' He pouted slightly. 'But.' John grinned at him; it was amazing how the guy could always find something. 'Petrified. That's the key, it's a very specific type of incident. No student could do that to someone and there's precious few spells that do that anyway.'

'So you reckon a teacher did it?' Asked John incredulously. Sherlock shrugged.

'It's more likely than student.' He muttered. 'But still improbable. I really need to get a closer look at the victim – see if there's any clues to how it happened.' John nodded to show he was following.

'Ok. So we need to break in to the Hospital Wing.' John stated. Sherlock looked at him blankly.

'Break in?'

'Yeah. The Head's of Houses just came round to talk to us all in the common rooms. You must have missed it cos you were here.' John gestured around the room. 'So Dumbledore told us that no one was allowed in the Hospital Wing, along with all the other new restrictions.' John grimaced. 'We have to be escorted to each class by the teacher!' Sherlock was silent for a moment.

'Well. Only one way to do it then.' He said decisively. John looked at him confusedly.

'Oh. Oh no. We are not doing that again!' He said shaking his head and backing away from the taller wizard as it clicked.

'Why not? It's the only way.' Sherlock stood up and took a step toward John who backed away even more.

'No. Sorry no. I am never ever doing that again.' The shorter wizard held his arms up in front of him. Sherlock stopped and sighed in frustration.

'Fine. Fine then. You hit me.' He stood loosely, and pointed at his face with one hand. John gaped at him.

'Seriously? You want me to hit you?

'Yes. I know you don't want to but come on, just do it.'

John laughed. 'Don't want to do it? No I'd quite like to hit you, but if I do I mightn't be able to stop.' Sherlock looked at him perplexedly.

'Why do you want to hit me?' He looked affronted.

'Has anyone ever told you that you're an annoying dick sometimes?' Asked John in mock curiosity. 'No. Look, can't you just cast a spell on yourself or something?' Sherlock glared at him, then whipping out his wand tapped it on his thigh menacingly. John flinched as the wand tip flashed past him.

'Nose-bleed? Too basic. Vomit? Too messy. Mutation? Could cause suspicion.' Sherlock muttered darkly to himself, pacing the small room and shooting pointed looks at John. The latter settled himself in a chair, pleased that he had got his point across. He hadn't fancied turning up at the Hospital Wing sporting an apparent example of muggle duelling again.

'How about an allergic reaction?' John suggested. 'You could have eaten some… I don't know, peanuts at lunch.' Sherlock gave him a withering glare.

'Peanuts?' He scoffed. 'Peanuts…' Staring into the middle-distance he repeated the word appraisingly. Then with sudden grin he turned to the blonde. 'John, you are a genius! Well, no you're not. But sometimes that average brain of yours comes up with fairly brilliant ideas.' Prancing across the room, the dark haired wizard ruffled his friend's hair rather too energetically causing John to wriggle away, and escape over to the other side of the room looking positively dishevelled.

'Yeah, thanks.' Muttered John, attempting to smooth his hair. 'Do you remember that conversation we had about compliments? How they're supposed to be nice to the recipient?' He tried to straighten his robes, looking across the room at the whirlwind of excitement that was Sherlock. The latter didn't even glance at him as he spun around the desks, waving his wand abstractly.

'Ok. So peanuts, swelling. Maybe Tumesco, or Conflunctious.' The Ravenclaw muttered to himself. John narrowed his eyes slightly; none of what Sherlock was saying sounded familiar.

'Sherlock. Wait. Are you making this up? You can't use a spell you've made yourself, it's not safe!'

'Yes I can. Creating a spell is basic, I'm sure even you could do it if you tried.'

'No. No, no, no. Sherlock, listen to me. How can you even know it will work?' The tall wizard sighed at him, rolling his eyes.

'Easy. An incantation is used as a tool for the wizard to concentrate his powers into a certain direction, much like how a wand is used, you don't need a wand but it allows for more accuracy and channels a wizards power. Any person with magical blood could in theory produce the desired magic without either a wand or an incantation. So, all I'm doing is providing myself with the necessary instruments.' Sherlock had gone into his monologue mode; barely taking breath the wizard stated his intentions to a rather perplexed John.

'The incantation must do two things. One: it must have some relativeness to the desired spell as my mind must be thinking of what I want the spell to achieve. Two: It must be more than normal speech, magic works best through a stronger language such as Latin. Therefore Conflunctuo, meaning to swell, and possibly coupled with Magnus, meaning large.' John looked at him, his mouth open. Sherlock looked back at him expectantly for a moment or two before sighing in exasperation.

'So… so, you're just finding some words that mean to swell up… and then…' John struggled to understand, if what Sherlock was saying was true, how come whenever he said a spell wrong the spell failed to work?

'Because you're expecting it not to work when you know you've said it wrong.' Sherlock stated. John sighed again, how did he do that?

'Right. Ok. Just don't test it on me first ok?'

'Don't need to. It'll work.' The Ravenclaw cleared his throat dramatically causing John to roll his eyes; then pointing his wand at his own face, Sherlock spoke quietly and clearly. 'Magnuso Confluctious.' There was a bang, a flash of magenta light and a squeal of pain from Sherlock. John rushed forward, blinking away the afterimage of light.

'Sherlock! Sherlock, are you alright!?' He pulled the latter's hands away from his face and stared.

'Ow. Ow, I did not calculate the pain levels quite correctly it seems. Ow.' Sherlock patted his face gingerly. The spell had done its job magnificently; the once thin, pale face was swollen to unrecognisable proportions, the skin was red and shiny, and his clever eyes had disappeared into puffed-up slits. Unable to stop himself, John started to chuckle, then slapping a hand over his mouth he dissolved into laughter and staggered, bent double to lean himself against the wall. Sherlock looked at him incomprehensibly. Catching his eye, John collapsed onto the flagstones in hysterical laughter, tears pouring from his eyes. 'Uh John? John, I don't understand. It worked, why are you laughing?.'

'Oh Sherlock.' John gasped, wiping tears from his eyes. He sat up, hiccoughing slightly, the main hysterics finished. Sherlock offered him a hand and hauled him up off the dusty stone, still peering at him through swollen eyes.

'I need to go now. The spell probably doesn't have a too long life.' He explained to a still quietly chuckling John.

'Yup. Yup, right. So what's my story?' He replied rather weakly.

'We were just chatting, then I went like this.' He gestured at his face. 'And you were - are worried that it might get worse so you're taking me to the hospital wing.'

'Just that?'

'What's wrong with that?'

'Well… It's a bit basic isn't it?'

'Only lies have detail.'

'Ok. If you're happy.'

'Not particularly.'

John opened the door and ushered a slightly unsteady Sherlock out.

'I can't see properly.' Sherlock hissed in irritation.

'Your idea mate.' John grinned, grabbing his elbow and leading him in the correct direction.