If a player wants to cast a spell, what is the first step they must take?

When a player wants to cast a spell, the first step they must take is to pay the mana cost. This is essential because casting a spell requires that the player has the necessary resources available to pay for it, which typically involves tapping lands or other permanents to generate the needed mana.

Once the mana cost is paid, the player can then put the spell on the stack, declare its targets, and follow through with the casting process. However, without paying the mana cost first, the spell cannot be cast at all. This mechanic ensures a balanced and strategic gameplay experience, as players must manage their resources effectively.

The other actions, such as declaring targets or putting the spell on the stack, occur in subsequent steps and cannot happen until the mana cost has been successfully paid. The initial act of paying the mana is foundational to the whole process of casting a spell in Magic: The Gathering.