Dan could see Phil waiting for him outside their potions class. He had changed into some dry robes after their lunchtime disaster. Dan chuckled slightly as he remembered Phil rolling down the bank. Phil smiled at him, bringing Dan to his senses. He stopped next to the classroom door. 

"You ready?" he asked. Phil shrugged. 

"I suppose." he muttered. 

"Are you going to stand around all day?" Phil jumped. Their professor was watching them from his desk. "Well?" Dan and Phil quickly made their way to their seats. 

"Today, we'll be making a slightly harder potion than what we've done before." Their professor continued. "The potion is known as Herbicide. Can anyone tell me what this potion is used for?" he asked. "How about... you?" he pointed a finger at Phil, who gulped. He knew what it did- he'd lost some of his plants when he mistook some Herbicide potion for water. 

"It kills or harms plants." he said, just loud enough to hear. The professor looked shocked for a moment, but managed to calm himself. 

"Correct, Phillip." he said slowly. "Five points to Hufflepuff." Phil sighed with relief. 

"I will be testing your potions at the end of class." their professor turned back to the black board. "Here are the instructions, which you can also find in your potion books. Begin." The sound of scraping chairs filled the room as the children made their way to the ingredients cabinet. Phil waited until most of the class had sat down again before fetching his own ingredients. He looked at the board. Lionfish spines... Standard ingredient... Horklump juice... Flobberworm mucus. Once he'd grabbed all he needed, he made his way back to his desk, then opened his potions book. It read: 

HERBICIDE POTION

Brewing intructions

1 x Flobberworm Mucus

1 x Horklump Juice

1 x Spines of Lionfish 

Standard Ingredient

1. Add 4 lionfish spines to the mortar

2. Crush into a rough powder using the pestle

3. Add 2 measures of Standard Ingredient to the mortar

4. Crush into a rough powder

5. Add 3 measures of the crushed mixture to your cauldron

6. Wave your wand

7. Leave to brew and return in 60 minutes

----------------------------------------------------------------------------------------------------------------------------------------

8. Add 2 measures of Horklump Juice to your cauldron

9. Heat to a medium temperature for 10 seconds

10. Add 2 blobs of Flobberworm Mucus to your cauldron

11. Stir 4 times, clockwise

12. Wave your wand to complete  the potion

Phil put his ingredients in order of use. He was going to get this right. He started reading the instructions again, making sure to read everything. Dan leaned over. 

"Hey, Phil, can I borrow some lionfish spines?" he asked. Phil continued to read, ignoring the people around him. Dan shrugged and grabbed some from the jar on Phil's desk. After he'd finished reading, Phil looked up. 

"Ok..." he muttered. He started following the steps, one by one. 

"Don't forget that you have a limited amount of time, everyone." The professor reminded them, placing an egg timer on his desk. Most of the class just nodded and continued, but Phil started to panic. He didn't have much time! He grabbed his pestle and crushed the Standard Ingredient and his already crushed lionfish spines into a rough powder, which was a funny shade of murky green. He added three measures into his cauldron quickly and picked up his wand. Just as the sand stopped falling, Phil waved his wand and a white light hit his cauldron. He'd done it. Their professor looked around, looking quite pleased. 

"It seems that you all managed it within the given time. Well done." he nodded slightly. "Now, while it brews, use this hour to put away what you don't need later and clear your mortars. Once you've done that, I want you to write a page of information about the Herbicide potion. The class groaned then did as they were told. 

An hour later, the class sat with slightly emptier desks and a piece of parchment with their work. Their professor peered at each desk.

"Leave your essays on the side of your desks, and I'll collect them later. Now, I want you all to complete your potions." He turned the egg timer upside-down. "Begin." The class started brewing once more, keeping an eye on the timer. Phil looked over at Dan who was already adding his flobberworm mucus to his cauldron. He turned to look at his own cauldron and picked up his horklump juice. He tipped the bottle slowly, allowing two measures to seep out. He shut the lid. He looked up at the timer. 30 seconds left. He looked at the board. 

'Heat to a high temperature for 10 seconds' he read. He used his wand to light a fire underneath his cauldron, willing it to heat faster. He waited as the potion started bubbling. Was it supposed to do that? He looked around. Everyone else's potions were complete. Perhaps it was meant to do that? He put the fire out and added two drops of the flobberworm mucus. A weird sizzling noise came from his potion, getting louder and louder. Most of the class had started putting their things away and were at the other side of the classroom. Only Dan and Phil remained at their seats. Phil stared at his cauldron. Was it... expanding? He gasped. Before he could warn anyone, his potion spouted from the cauldron, hitting the roof and landing on the empty desks around him. Dan gasped beside him, and Phil turned to see Dan covered in green goop. Their professor walked over quickly. 

"Phillip, would you kindly read step 9 from the board?" he asked. Phil nodded. 

"Heat to a m-..." He froze. "Oh..." he looked at his wrecked cauldron. Dan shrieked behind him. "Wha-" Phil turned and stared in disbelief- plants had started sprouting all over Dan, wherever the potion had hit him. His hands, face and robes were now covered in plants. Grass, weeds, moss. He looked down at his own robes. He too was covered in plants. He sighed. 

"To the hospital wing, both of you." their professor frowned. Phil looked at the floor as he passed his classmates and made his way to the hospital wing with Dan for the second time that school term.