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Recently I made a deck to have fun with when I play with family/friends. So I played Curse of Misfortunes on target player, and he simply didn't understand the card, saying "Why did you cast this on me? when I don't have any curses in my deck? You're supposed to cast it on yourself so that you can use it." So I told him why would I want to curse myself? and add more curses to myself? So he then asks "I don't understand this card. Henceforth I won't be getting any curses from this card unless you can prove it" I tried to explain it by telling him that I get to pull curses from my deck and give it to him. And that there is a difference between this curse and other curses, because the other curses say Enchanted player gets this and that. While Curse of misfortune doesn't say any of that so it means that I get the ability of that card to place curses on him. So he simply said the same thing and didn't understand it. So I questioned myself too, therefore me asking this to you guys.
Another question, If I play curses on players, are those enchanted cards still considered mine? Ex. I play a curse on target players, and I have Sphere of Safety out, and a player attacks me. Do they have to tap as many mana to as many curses I've given?