Cards are rated on a scale of 1 10 and the difference between a 9 and a 10 can add hundreds or thousands of dollars to a card's value
Once these cooldowns have refilled, they'll stay that way until you spend them, they won't continue to accrue
Magic The Gathering (and Dungeons & Dragons) publisher Wizards of the Coast have the finances and scope to explore third party IP such as Warhammer and The Lord of the Rings, and as the 30th anniversary of Magic: The Gathering approaches theres plenty of other compelling content in the works, including an already revealed 30th anniversary Secret Lair countdown calendar, to be opened like an advent calendar during December
Oh, and it costs a thousand dollars
Read More: Wilds of Eldraine Brings Back Manlands With Spicy Rare Cycle #4 Horn of Valhalla If you have a deck designed to go wide with lots of small Creatures, Horn of Valhalla is a great addition
The best thing about the card is that no one knows what anyone else has in their hand