Its front face, which is marked with a sun symbol and has a mana cost, is the default
The other players can often slow you down so Wizards likes to give the strategy a few noncombat options to add poison to opponents
Just having Inti around means that it gets stronger each turn when attacking, and you have a baseline 2/2 that already attacks as a 3/3, not to mention synergies with unblockable creatures or big, fatty green creatures
Play boosters contain 14 cards with a set distribution of common, uncommon, and rare/mythic cards, along with land and wildcards
That is really useful, not to mention the option to crack to blank a graveyard
It also really helps ensure that you know what cards we have our eyes on so cards won't feel like they're banned out of nowhere in the future