Collected Conjuring

• WWizards of the Coast2019-06-14
  Official Ruling
  If a spell has in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.
• WWizards of the Coast2019-06-14
  Official Ruling
  You may cast the two sorcery cards in either order. The second is cast before the first resolves.
• WWizards of the Coast2019-06-14
  Official Ruling
  Each individual spell you cast this way must have mana value 3 or less. Their total mana value could be greater.
• WWizards of the Coast2019-06-14
  Official Ruling
  You must cast any of the exiled cards you wish to cast while Collected Conjuring is resolving. You can’t cast them later in the turn.
• WWizards of the Coast2019-06-14
  Official Ruling
  If you cast a card “without paying its mana cost,” you can’t choose to cast it for any alternative costs. You can, however, pay additional costs. If the card has any mandatory additional costs (such as that of Tormenting Voice), you must pay those to cast the card.

Rulings via Scryfall