Draft Boosters have a fixed distribution based on rarity. Currently, a regular booster pack contains sixteen cards: fifteen playing cards and a marketing card / . Of the fifteen playing cards, one is currently a basic land, ten are common, three are uncommon, and one is rare or mythic rare.
How many basic lands does a Cube need? 30 to 40 of each type is plenty for an 8-player draft. In a typical cube that supports 5 colors split among 8 drafters, it's unlikely more than 2-3 drafters end up in the same color.
How to draft: First, players sit around a table in a semi-circle. Each player then opens a booster pack and picks a single card without showing the other players. Each player then passes the remaining cards to the left, and continues drafting from the new cards they get from the player on their right.
In MTG Arena drafts, lands work a bit differently than in your usual kitchen-table Magic. When you're drafting, you don't have to pick basic lands during the draft portion; instead, you can add any number of basic lands to your deck after you've picked your cards.
Booster Draft rules allow you to add as much basic land (only plains, island, swamp, mountain and forest) as you want to your deck and require that the deck be at least 40 cards. The standard number of lands in a draft deck is 17–18.
Deckbuilding is a little different in Draft because your final build will only be 40 cards. You should choose 23 spells from your card pool and then you build a manabase of 17 lands that will be provided to you. You do not need to draft the basic lands you put in your deck!
You, along with everyone else at the table, open one pack each and select—"draft"—one card from that pack. Then you pass the rest of the cards to the player on your left. The packs get passed around the table until all the cards are gone. You repeat this process for the second pack, passing to the right.
To have a Booster Draft, you need three things: 3 Booster packs per player from the current draft format. 8 total players (It's possible to draft with fewer than 8, but 8 is the number needed for sanctioned Magic drafts) A healthy supply of basic lands.
The Draft format is a true test of skill. Build decks on the spot from a rotating selection of booster packs. Pick a card and pass it on. Harness the chaos, explore emergent strategies within the cards your opponents pass you, and draft a unique and exciting deck.
Keep in mind that you're not allowed to look at your cards during the drafting process and after everyone is done drafting the first pack, there is a 90 second review period where you get to look at all the cards you've drafted.