Counters, noncombat damage, targeted spells, you name it
it brings some really interesting concepts to the game and not just brilliant art
Its one of the few mechanics in MTG (alongside planeswalker emblems) that spells, cards, and effects cant interact with directly
For less flexibility (Ancient Grudge, Ray of Revelation, Divine Offering) you tend to get card advantage or some other upside
Liliana of the Veil As a discard tool Liliana is kind of weak yet she remains atop this list because the function of the card as a whole is so rounded and effective
"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." You must still follow any timing restrictions and permissions, including those based on the card's type