BNG: Expected numbers of copies of a card

In triple Theros, an 8-person draft had an average of 2.4 copies of a given common, 1.2 copies of a given uncommon, 0.4 copies of a given rare, and 0.2 copies of a given mythic. Now that we’re down to 2 packs of Theros, we have fewer of the key cards for our familiar archetypes.

An 8-person BNG/THS/THS draft will have 2/3rds as many copies of a Theros card at a given rarity: 1.6 copies of commons, 0.8 copies of uncommons, 0.26 copies of rares, and 0.13 copies of mythics. While there are half as many Born of the Gods packs as Theros packs, the draft won’t just have half as many copies of a given Born of the Gods card at the same rarity since the set has a different rarity distribution (60 commons, 60 uncommons, 35 rares, and 10 rares). Instead, it will have an average of 1.3 copies of a given Born of the Gods common, 0.4 copies of a given uncommon, 0.2 copies of a given rare, and 0.1 copies of a given mythic.

This means that while you will see 1/2 as many copies of a given uncommon, you will actually see about 3/4ths as many copies of a given Born of the Gods rare or mythic, and 0.85 as many copies of a given common, which is more than you might have expected. In fact, if a given Theros common has a very close analog in Born of the Gods, it means you’ll now have access to 2.9 copies of the card instead of 2.4 copies.

In future weeks, we’ll use this information, along with the prior analysis of what cards each THS/THS/THS archetype gains, to determine where the prior archetypes have gained or lost with the introduction of Born of the Gods.