I suppose I'm "supposed" to give you all a small backstory before I ask the question?
When I was young I used to play MTG with my father. I loved playing it since was possibly the only game he played with me on during my childhood after he became disabled. Eventually he told me he was bored and tired of the game and I was unable to truly play it ever since. However, because I liked the memories and the art styles of the cards I still bought card packs and collected the cards.
Well, some time passed, I gave up in ever playing the game again and now I'm a senior in HS. Apparently, for a reason only god knows of, the people in the school I'm at started to get into card games of the sorts. Poker, Bullshit, BlackJack (a personal favorite of mine), were common but now I'm seeing multiple people playing Yu-gi-oh and MTG. It's reached a point where they are even added onto the school "Ban" list for cards (though nobody gives a shit and everyone is still playing cards).
"I'll put a cap in yo ass" is turning into, "Bitch, I'll duel your ass and then we'll see who's laughing Nigga."
Not the point though...
The point is...
Today, someone I despise (Though I am trying to be more "nice" to him due to a promise I had with my sis) said that he could beat me in MTG. Note that most duels I win thanks to my Draconic deck and I allowed him to look at my cards while I was looking at his. His Deck was a badly built poison deck of nothing but green cards that focused too much on counters and had a bunch of random things like death touch, haste, reach in it. Usually that's okay but this deck was built purely for the single chance that he had a perfect hand and really great luck. Personally the most of the same type of card that he had was two and the strategy he planed on using was risking way too much on good luck.
Now while I was looking through his cards, I've seen one that I actually liked. a 15/15 creature that has devour, trample AND adds 3 3/3 token creatures when it dies into play. I told him that he has some good cards but overall his deck sucks more dick then the occasional prostitute. While he was looking in my deck he found a laminated card of mine that holds a fair amount of importance in my deck but was also one of the very first cards I've gotten... which means it was the main one I would play when I played with my father when I was younger and it does hold some sentimental value due to that exact reason. He bargained and asked for a "Fair" Trade for it and I refused him. In a Final attempt to try to get this card of mine he told me that he'd duel me for it and that if I win I get a card of his of my choosing. Before I could answer I got saved by the bell and so I told him I'll think on it.
Because his deck is comparable to literal shit, I know the chances of me winning are relatively high. However should I risk losing one of the cards that me and my father used to play with, and the card I almost won him with on the last time we've ever played a game together? Even then, should I take advantage of his weakness and basically steal this idiot's card since I know he'll lose? (unless he gets a good hand) Let's see what answers (or randomness) spam shall come up with.
This is one of the very few times that I'll turn to spam's opinion on something that has to do with my personal life so don't get your hopes that this will become a new thing for me. Reason why I'm asking here is because I have multiple people here who I consider friends and would like to hear not only theirs but the publics opinion on this.

