Its like starting the game with an extra card in your hand
The Dimir Deck Source: Reddit Like the lands, most of these Magic cards are fairly weak, as is to be expected from Starter Decks
Multicleave is an optional additional cost
It's an aptly-named card, since it's mostly commonly seen producing infinite combos with Sensei's Divining Top and a cost reducer
Each Unfinity Draft Booster contains 14 Magic cards, 1 Sticker sheet, and 1 ad card/token, with 1 Rare or Mythic Rare card, 2 Attraction cards of any rarity, 3 Uncommons, 7 Commons, and 1 Full-Art Space-ic Land card (Planetary land in 72%, Showcase Orbital land in 24%, and shock land in 4% of packs)
Keith Adams have stated that many of the playtest decks he has found contained zero rares (and there weren't that many pre-alpha playtest decks to begin with after all)