Weeks of observing the Weasley twins had taught Daphne and Tracey at least one thing, the life of a professional prankster was a nervous one. Over their years at Hogwarts, the twins had more or less pranked everyone in the school and many people would be very eager to get them back as a reprisal. True, in spite their tendency to prank, they were quite well liked in their own house and amongst some people outside their own house, they possessed boyish charm that made a lot of people forgive and forget quite easily. But particularly in the house of Slytherin, who were often the target of their more severe pranks, they were actively hated by some.
The fact that the twins were not subjected more to revenge came down to two things. Firstly a lot of people did not want to start a prank war with two people that were clearly devoted to pranking and that practically turned it into a lifestyle. Nobody wanted to go toe to toe with two full time jokers that were clearly very creative in this area, some Slytherins might even call them sadistic.
Secondly the twins, being so observant of opportunities to prank others, were also extremely aware of ways they could be pranked themselves and careful in their own day to day activities, you could call them paranoid. Tracey made an astute observation when she pointed out that nobody could keep up those stress levels: "I am telling you, before the end of Hogwarts those two will have suffered some kind of nervous breakdown. I wager they will drop out of school or something like that, if they are not expelled first."
How did this paranoia manifest itself? Well, for example, being a pair, the twins divided their time in such a way that one of them was always on the lookout. If Fred was reading, George was glancing around. If George was eating, Fred was observing the surroundings, only stopping momentarily to cast detection charms on the food that was on the table to check for potions. This hade made observing them a risky operation for Tracey and Daphne. They also had a procedure for walking through any door that involved a mirror on a stick and some kind of listening device. When they had quidditch practice, they warded the doors and windows of the dressing room so that no one could tamper with their possessions. In short their life goal was: to prank and not be pranked.
Still, the cautious study of the Weasley brothers that Tracey and Daphne had undertaken had led them to a possibility. Part of the twins' anti-prank measures was the fact that they only carried one school bag between them, they were together always anyways and it was easier to keep your eye on one bag instead of two. This brown, leather worn bag was closed with double straps and, as you can guess, charmed with protective spells that had to be meticulously removed and replaced whenever something was needed from it. However, the girls had observed one period during the day when these particular security measures, were followed with less discipline.
The life of a prankster had to be financed and the twins did this by some general wheeling and dealing on the Hogwarts black market. This mostly took place in the half hour before dinner at the Gryffindor table in the great hall. The twins would usually sit at the far end of the table, removed as far as possible from the staff's table, where they were approachable by their 'clients'. They usually had some betting pool going on, or they supplied some smuggled firewhiskey to spice up a party, any illegal item could be ordered really. Sometimes they even operated as 'hit pranksters' when they were approached by a student that wanted to hire them to get back at a rival.
During this time their schoolbag was left open and without protective charms more than at any other point during the day. They had to take stuff out or put something back constantly, which made it impractical to remove and recast their normal charms. Also, both boys usually were quite excited during these activities and let their guards drop a little. Whatever attention they had left went to observing that no teachers approached during their dealings.
This, the girls had decided, would be their window of opportunity and they had started to devise their plan from there. They had begun to gather information and had to run some errands here and there to gather some favours. Since they were first years, they had needed help with subjects and spells that were only taught later, but eventually they had learned from their school mates, they had practiced and prepared until everything was ready. Now, they were going to explain Dread what his role was going to be.
They were sitting at the Slytherin table twenty minutes before dinner time, with Daphne facing the Gryffindor table at the other side of the hall and Tracey sitting opposite of her. As usual the Weasleys had opened shop at their spot at their house table, placing them in the corner of the great hall. Daphne had Dread safely tucked away under her left arm and was talking quietly to him in his ear. "Dread, my sweet crow, do you see those two boys sitting at the table there? Do you see the bag which is placed on the floor next to the table? We want you to fly over there and drop this stone in that bag."
Tracey put a stone that had runes carved into it on the table, pointed her wand at it and whispered an spell, a soft blue glow showed that the runes had been activated. Then she placed the stone carefully in front of Daphne and Dread.
"This, my sweet Dread, is a stone with an expulsion rune carved into it. When you drop it in the bag, we, along the rest of the great hall, will be able to discover what kind of equipment those two maniacs have stuffed away in there. Do you think you can drop the stone inside? You will have to aim carefully and time well."
Dread stroked his beak and head against Daphne's arm, which was his usual way of indicating he understood the task at hand.
"Now, before you go, I will cast a disillusionment charm on you. This will make you less visible, especially if you stay high near the enchanted ceiling. It will feel strange for a moment, there will be a cold feeling running over your body, but do not be afraid. Are you ready for it?"
Again dread confirmed that everything was clear. Daphne whispered the charm while pointing her wand at the crow and he became nearly invisible. It was a difficult charm, particularly for a first year, but it required less power on smaller objects and Daphne was quite a powerful caster for her age, especially when she felt her familiar nearby. She had trained last week on little practice balls, helped by Ophelia Woodhouse, a sixth year in their house.
Tracey had been in charge of making the stone and had had help from a fourth year called Thomas Wolf. Even though he was only in his second year of ancient runes, he assured them the stone would work. Around the expulsion rune that would start throwing out he schoolbag's contents, they had also carved a set or runes that would delay the activation for about five minutes and that would increase the strength of the charm progressively, in case there were some heavier objects in the bag.
Picking up the stone in his right claw, Harry took off and took up position on a high vantage point. He felt excited, it felt good to undertake a project together with Daphne and Tracey. It reminded him of the expeditions he and his crow friends often undertook, every member of the group had its part to play and they reached success together. Sure, he recognized the boys, they were the ones that had been after them the last months, he was happy to return the favour.
He spotted an opportunity, apparently a Ravenclaw had ordered a larger item and Fred was taking a long box out of their bag. When he turned away to hand over the item, Harry took his chance, he flew over to them and with a small dive he aimed and dropped the stone. His aim had been true, it landed in the schoolbag and Harry turned around in the air, flew back and landed next to Daphne. She took him back under her left arm, lifted the charm that she placed on him and slowly started stroking his back. She whispered, "Did you hit your target? Very good Dread, now soon we should see some interesting results."
More and more people started entering the great hall and were sitting down at the tables, most of the teaching staff had also gathered for dinner. Then it began. When George put away his 'book of bets' in which he kept payments for their betting pool, the small yellow booklet immediately flipped back out. Frowning, George stacked the booklet away again, but this time it simply shot out of the bag, flying a few meters in the air. It was immediately followed by some loose pieces of parchment, a transfiguration book and three chocolate frogs that started jumping away. At this point the twins glanced at each other briefly with a panicked expression.
But before they could jump into action, the bag started expelling even more of its contents, the second wave included some more books, a couple of empty potion bottles that smashed on the ground and five dung bombs that were thrown in all directions and promptly activated. Chaos started to develop as people jumped up to get away from the stench and the flying objects. George tried to close the bag while shouting to Fred, "The map, find the map!". Fred started crawling around on the floor frantically looking for something.
But George was unable to close the bag, a third wave threw an ever bashing boomerang, a couple pieces of firework, which naturally activated and some quidditch gear in the air. At this point most of the hall, including Daphne, Dread and Tracey had ducked under their tables for cover. The shouting and screaming around them was deafening. Tracey called to Daphne "Wow, I did not expect their bag would contain that much!". Daphne replied: "Yes, I hope we did not overdo it and end up in trouble. The bag must have been equipped with some pretty heavy expansion charms.", a suspicion confirmed when a complete cleansweep 7 shot out next.
Meanwhile at the staff table Professors McGonagall and Snape tried to make their way over to the far corner of the great hall, while the rest of the staff, including Headmaster Dumbledore, tried to calm the students down and stop the several magical items that were flying in the air. Things escalated one more time when a bag of Peruvian instant darkness powder was thrown in the air and opened, momentarily obscuring the hall. But Snape dealt with this new development quickly by casting a counter spell. When he and McGonagall finally arrived near the Weasley twins, she was able to cast a powerful closing spell on the bag which finally stopped the supply of mayhem, while Snape grabbed the two unfortunate twins by the shoulders.
When the rest of the staff had eventually gotten all the other magical items under control and it appeared no one was seriously hurt, Dumbledore grabbed the attention of everyone. Even after all this, he still had a smile on his face and a twinkle in his eyes. "That was quite the display, I never thought I would see that many Zonko products flying around in the great hall at the same time. But I must admit that the hall is not in a condition to host a dinner right now. Why don't you all go to your common rooms and we will arrange for some food there. Except for you Mister and Mister Weasley, why don't you join me in my office for a moment?"
Gathering themselves all students starting making their way to their houses. While Fred and George started walking over to Dumbledore with their heads lowered. Tracey whispered to Daphne: "That went better than we thought. We pranked them good those boys."
But their enthusiasm was greatly reduced when they passed Professor Snape on the way out, he was by now standing near the great entrance doors of the hall and stopped them for a moment. "Miss Davis, Miss Greengrass, why don't' you come to my office after dinner? I think we might have some matters to discuss. Oh, and bring your crow."
Both girls gulped and responded in unison: "Yes Professor Snape." It seemed like they were not yet in the clear.