36 booster packs per box. Each booster pack comes with 15 cards.
This set contains many great cards, such as:
Karn, Scion of Urza
Mox Amber
Teferi, Hero of Dominaria
Lyra Dawnbringer
Muldrotha, the Gravetide
History of Benalia
Jaya Ballard
Jhoira, Weatherlight Captain
Damping Sphere
No card is guaranteed in a booster or box but these are some of the great cards you could get.