Explore is less reliable but more relevant in the late game
Rather than writing everything out, using multipliers, and doing all of the stuff we do for the article, you can simply add up the total value of all the mythics in the set (in this case, roughly $115), divide by the total number of mythics in the set (generally 15 but sometimes slightly different Throne of Eldraine has 15, which would give us $115.05 / 15 = $7.67) to get the average value of a mythic rare, and then finally multiply by the number of mythics you'll get from an average box (here's a cheat sheet: the average box as 4.5 mythics, 31.5 rares, 108 uncommons, and 360 commons)
The cards will come in a 4-card promo pack, with one holofoil included in each pack
You will likely have enough for two dual-element decks if you run 20 Sites per deck (below the current official minimum), but you probably wont have enough for a legal constructed deck with 30 Sites
Exalted Sunborn is a great variant on this effect, attached to a creature that could be cast temporarily for two mana
For example, it stops cards like Collected Company or Birthing Pod