In a normal set, a normal rare has about a 1/50 chance of being pulled while a mythic has about 1/120 (1/8 chance of getting one of fifteen mythics).
In this set, any card that appears in exactly one pack list has a rarity comparable to a mythic while those in two pack lists have rarity closer to (but slightly worse than) a rare... regardless of the rarity on the card.
As such, Selvala (a mythic) is effectively a rare while Rhystic Study (a rare in this set) is effectively a mythic. That is kind of bonkers, right?
In a normal set a rare appears twice in every 121 packs while a mythic appears once in every 121 packs. Those are exact figures for 'normal' sets... things like 'a legendary in every pack' sometimes modify that, but generally they aim for those values even then.
In Jumpstart the new cards appear at roughly those rarities as well (new mythics appear one in every 121 packs, new rares twice in every 121 packs) while reprints can appear above or below those figures with no attempt to keep them in line. However from what I have seen mythics are still appearing 1 in 121 and rare reprints at 1 in 121 or 2 in 121. In this case both these are appearing 2 in 121, so the rare is on target and the mythic is effectively downgraded to rare.
New Commons and uncommons are being printed at roughly normal rarity (I think that means a common has to appear in 12 lists and an uncommon has to appear in about 4.5 lists). Again reprints can be way off this metric.
This set does not seem to have foils so your odds of pulling a given rare or Mythic are slightly lowered again. Likewise we don't now if there is any sorting in the boxes to prevent duplicate packs (I assume there is). I believe part of the gimmick is mixing 2 tribes together so they probably want to avoid people mixing Elves with Elves and the like, so there is also probably less variance in the distribution of the cards and the value of the box.
This set does not seem to have foils so your odds of pulling a given rare or Mythic are slightly lowered again. Likewise we don't now if there is any sorting in the boxes to prevent duplicate packs (I assume there is). I believe part of the gimmick is mixing 2 tribes together so they probably want to avoid people mixing Elves with Elves and the like, so there is also probably less variance in the distribution of the cards and the value of the box.
Http://www.fantasticneighborhood.com/
Comedy gaming podcast. Listening to it makes you cool.