Draft Boosters are the original booster packs from the onset of Magic: the Gathering. For most of MTG's history, sets only offered Draft Boosters. Prior to the introduction of Theme Boosters in 2018, the common name for Draft Boosters was "booster packs"—there were no other kinds.
While today's Draft Boosters contain 15 playable cards and a marketing card or token, this was not always the norm. In the early days of MTG, multiple sets came in booster packs with less than 15 cards.
As MTG evolved as a trading card game, so did its booster packs. Wizards of the Coast made periodic changes to booster pack card counts and inclusions. To better understand the variations in Draft Boosters between sets, let's start from the beginning.
Booster packs from Alpha, Beta, and Unlimited contained a mix of cards and rarities. Their pack contents were one rare, three uncommons, and 11 commons with the chance for a basic Island to replace a rare. Revised didn't have the rare replacement issue, but basic lands could appear in other card slots. WotC stopped including basic lands in core set booster packs between 4th and 6th Edition.
Some early MTG expansion sets received different booster treatments than core sets. Arabian Nights, Antiquities, The Dark, and Fallen Empires came in eight-card booster packs. Surprisingly, booster boxes held 60 of the eight-card booster packs.
There were six commons and two uncommons in eight-card booster packs. The rarities between commons and uncommons varied. According to Crystal Keep, a common card with a C4 rarity appears four times on the common print sheet of a set. A U3 rarity means that an uncommon card appears twice on the uncommon print sheet. The same rules apply for cards designated as C3, U2, etc.
Cards with a U1 rarity are deemed "rares" since they appear once on the uncommon print sheet. Arabian Nights was the only eight-card booster set that did not have any U1 rarity cards. WotC quit producing eight-card booster packs after Homelands in 1995.
While WotC was retiring eight-card booster packs, they introduced 12-card booster packs with Chronicles. Each Chronicles booster pack contained nine commons and three uncommons. Chronicles booster boxes held 45 booster packs, nine more boosters than the Draft Booster boxes sold today.
About a year after Chronicles' introduction, WotC tried offering 12-card booster packs for Alliances. The makeup of Alliance booster pack card rarities differed from Chronicles. Alliance booster packs held one rare, three uncommons, and eight commons. Force of Will, likely the most well-known card from Alliances, was only an uncommon (U2). Following Alliances, 1990s expansion set booster packs held 15 cards with one rare, three uncommons, and 11 commons.
Urza's Legacy, released in 1999, was MTG's first set to offer foil premium cards in booster packs. The pull rate of foil cards in Urza's Legacy was 1 in 100 cards. Finding a specific foil rare in an Urza's Legacy booster pack was extraordinarily rare. The low probability of pulling a foil Grim Monolith from a booster pack is one of the reasons why it sells for thousands of dollars today.
7th Edition foil cards were unique. 7th Edition was the first core set printed with foils and the last core set with old card frames. The set contained many classic MTG cards, including Birds of Paradise, City of Brass, Serra Angel, and Shivan Dragon. Regular versions of 7th Edition cards had white borders but, foil versions of 7th Edition cards had black borders.
Foil cards became more frequent in booster packs over time. Torment was the first set to change the pull rate of foil cards from 1 in 100 to 1 in 70 cards. With help from the magicTCG subreddit community, it was determined that the pull rate remained 1:70 through Future Sight. WotC switched the foil pull rate to one in 56 with the release of 10th Edition. Foil pull rate modifications get tricky after 10th Edition. The below chart shows foil pull rates of typical sets between 1999 and today.
As you can see, the foil pull rate has been one in 45 cards since Core Set 2020.
Interestingly, Time Spiral was the first set where the foil card no longer replace a card in a booster pack of the same rarity. The foil card in Time Spiral booster packs replaced a common, thus creating the opportunity to find multiple rares in the same pack.
Beginning with 10th Edition, WotC added a marketing card as the 16th card slot in booster packs. The backside of the 10th Edition marketing card had either a token image or game rules. 10th Edition booster packs contained one basic land, one marketing card, 10 commons, three uncommons, and one rare. An 11th common replaced the basic land slot in expansion sets leading up to Shards of Alara. WotC continues to swap card slots depending on the set, but today, 16-card Draft Boosters are the mainstay for Standard sets.
Mythic rares first appeared in Draft Boosters with the release of Shards of Alara in 2008. The probability of pulling a mythic rare instead of a rare in a Shards of Alara booster pack was 1 in 8. WotC maintained the likelihood of 1 in 8 to receive a mythic rare from a Draft Booster for over a decade.
Last year, WotC changed the mythic rare pull rate upon the release of Zendikar Rising. The probability of finding a mythic rare in a Draft Booster from Zendikar Rising or later is 1 in 7.4. As a percentage, the chance to pull a mythic rare in a Draft Booster increased from 12.50% to 13.51%.
Modern era Draft Boosters do not always contain a marketing card or token, basic land, ten commons, three uncommons, and a rare or mythic rare. Shadows Over Innistrad utilized a dedicated double-faced card slot to guarantee at least one doubled-faced card in each Draft Booster. WotC ensured that every War of the Spark Draft Booster included a planeswalker. While not a massive shift, Guilds of Ravnica replaced the basic land slot with Guildgates.
WotC continues to innovate and evolve Draft Boosters each passing year. More recent examples of innovation are the dedicated Draft Booster slots for modal double-faced cards in Zendikar Rising and Mystical Archives in Strixhaven: School of Mages. Also, Mark Rosewater's article, State of Design 2021, talked about players enjoying Strixhaven's bonus sheet of Mystical Archive cards. It would not be surprising if WotC tries new methods of incorporating bonus sheets in upcoming sets.