You can build Smagol, Helpful Guide around a mix of aristocrats and The Ring tempts you, which can make for some silly (but fun) gameplay
You cast the copy while Mysterious Stranger's last ability is resolving and still on the stack
Unless it has flash, you'll most likely only be able to cast it during your main phase while the stack is empty

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Monarch in MTG: Quick Overview Monarch is a player designation that basically translates to, Draw a card at the end of your turn for as long as youre the monarch. You become the monarch by casting a card that makes you the monarch, but an opponent can become the monarch if they deal you combat damage
Thought Scour Thought Scour was once the premier cantrip for graveyard or delve decks, but that time has since passed (altough it still ranks highly among the most disturbing pieces of Magic art)