(2022-12-08) "Flashback [cost]" means "You may cast this card from your graveyard by paying [cost] rather than paying its mana cost" and "If the flashback cost was paid, exile this card instead of putting it anywhere else any time it would leave the stack." (2021-03-19) You must still follow any timing restrictions and permissions, including those based on the card's type
These colors tie to treasure creation, payoffs for spending mana from treasures, and artifact sacrifice
For a while, Ramp;D used a term "marquee card" which meant it was a splashy card that drew a lot of attention to itself and did something that had never been done before
Smothering Tithe in particular plays very nicely with this card, letting you draw a card on each players turn in a Commander game
While you can have four of any legendary in your deck, don't forget that if you end up with multiples with the same name in play, you'll have to choose one to put in the graveyard