"Welcome to your first Hunting class"(Supernatural // Harry Potter crossover)

DAY 3

"... but speaking of weapons, those that can actually kill a demon are pretty limited edition. Luckily we've got most of it here. Angel blades will work on demons ; to be honest they work on pretty much everything" – Dean said, grabbing the dagger and raising it high in the air for the students to see – "but me and Sam prefer using this little thing."

He picked up a knife that was lying on the desk. It was the size of a kitchen knife, with a wooden handle and a sharp-pointed, curved blade bearing some strange engravings. The metal gleamed faintly as he turned it in his hands absent-mindedly.

"This knife is one of a kind, you'll never see another one like it. Made our lives a whole lot easier, too. Ironically enough, it was a demon who gave it to us."

A girl raised her hand. "Sir ? If this knife kills demons and you hunt them down... Why did that demon give it to you in the first place ? It sounds almost suicidal..."

Dean snorted but his jaw clenched, and the brothers' faces darkened slightly. Ruby's treason was something they would probably never get over.

"Long story. Let's just say she seemed pretty friendly at the time, and Sa- we thought it was a brilliant idea to give her a chance and trust a goddamn demon. She said she wanted to help us defeat... whoever it was that we were trying to defeat at the time, so she gave us her knife to prove that she was on our side. Of course it eventually turned out that she was playing double and completely bullshitted us the whole time, but hey at least we got the satisfaction to kill her with her own blade !" he said with a smirk, making the students laugh. "Yeah... Moral of the story : don't trust demons. Never, ever trust any kind of black-eyed son of a bitch who tries to sell you his services. It never ends well, believe me."

"Anyway, this knife is probably the weapon we use the most, after our guns." Sam said. "But as we told you, there's only one knife like this on Earth. So, the most useful thing we can teach you today is how to slow down, trap and exorcise a demon, since you probably won't be able to kill them, if you ever meet one."

He pulled out a big plastic can filled with water from under the desk.

"There are several ways you can defend yourself from a demon, but the most common is holy water. It burns them like acid ; not enough to kill them, but enough to slow them down. It's also a good way to recognize them : in case you're not sure whether the thing you're facing really is a demon or not, throw some holy water at it. If it burns, bingo ! You could also use holy oil : set it on fire and it gives you holy fire, pretty badass. But it's really rare..."

"Holy oil is very difficult to find" Castiel interjected, frowning. "Our resources are far from unlimited, and only certain places in the world can provide us with it. As helpful as it can be to fight demons, I suggest we keep using holy water as often as possible."

"True. You heard Cas, guys : holy water is the best way to go. Turning normal water into holy water is really easy, just throw a rosary in it and say the words : 'Exorcizo te, creatura aquae, in nomine dei patris omnipotentis et in virtute spiritus sancti'. Yeah, you might wanna write this one down..."

After a minute of shuffling and bag-searching, every student had a blank piece of parchment ready and Sam repeated the spell.

"There you go. Also, remember salt and iron, that we use against ghosts ? Demons don't really like it either." Sam said.

Walking up to the blackboard, he waved at Dean's drawing : a huge pentagram inside a circle, completed with a few dots and symbols.

"Alright so, Dean, can you explain what this is ?"

"Sure I can. It's a Devil's Trap. You draw this on the floor and any demon who puts a foot inside the pentagram is instantly trapped. You can also draw it on the ceiling and it will trap the demons who walk underneath it. They can't get out of the circle, their powers are disabled and you can do pretty much whatever you want with them. Just make sure the paint doesn't rub off, 'cause if any of the lines in your drawing is broken, the demon will stay at full power and he'll be able to escape." Dean explained, rubbing off a patch of chalk on the side of the pentagram to illustrate his words. "Also he'll be super pissed because you just tried to trap him and he'll go twice as hellish on your ass."