Since they revealed most of the Mystical Archive bonus sheet, it's a good time for a reality check of how often all those chase mythics will show up.

7/8 packs will have an Uncommon SOA card In that 1/8th pack you have slightly less than 1/4 of a chance of a mythic and the rest are rare

Compare this to the original Strixhaven Draft Boosters:

Where Mythics were over twice as common and Rares almost 3 times as common

So the pull rates of the best cards have been heavily nerfed

Sourced from the bottom of the collecting article for SOS and the one for original Strixhaven