It can come out on turn 0, but since it only has 1 power, you need to build the deck with precise calculations to deal 20 damage, considering you're adding one attacker and you almost certainly need 4 copies, which risks drawing duplicates of a legend
Meanwhile, according to the odds provided on Collector Booster boxes ready for pre-order on Amazon, you have a less than 0.00003% (around 1 in 3 million) chance to open this precious card in a booster
Another site that can be used for raw cards, but much better for graded cards is PriceCharting
Its the kind of card that could easily double or triple in price in a few years once its out-of-print and people reflect on the best cards of the Scarlet & Violet era
But Vadrok, Apex of Thunder looked perfectly designed to make use of it
In cEDH, cards like Grim Monolith are often used in infinite combos