Once acquired, a card pack may be opened at any time. Waiting will not change them. Opening a card pack provides a fixed number of random cards, generally from the same [[Portal:Cards|card set]]. These opened cards may be new for the player, or already owned ("duplicates" or "dupes").

The contents of the pack some packs, e.g. Elite packs, are fixed when they are awarded or bought. Waiting to open them will never change what sets or card groups their contents may be drawn from. The contents of other packs are determined when opened, so what determines the contents may change before it is opened. I.e., cards from new sets may be added to the possibilities, and cards from [[Standard]] that rotate out to [[Legacy]] may be removed, and some pack contents are purposely preserved. Information about what a pack will and will not contain is usually found first, and first hand, from [[Coalitions]] and MtGPQ Discord channels, or the [[Elite pack tracking]] articles.