There are certain circumstances under which spell cards can be used outside of combat.
Any time a spell card is cast outside of combat, that spell card is exiled. Exiled spells cannot be used in or out of combat for the rest of the game session.
A player may choose to sacrifice a spell from their library in order to gain mana. In this case, the player will gain mana equal to the color and amount of the mana cost to cast the spell. Colorless mana will be added into the mana pool as colorless mana. Land cards cannot be sacrificed in order to gain mana.
When a spell is sacrificed, the spell's card is exiled from the players library for the rest of the gaming session. A spell that is exiled cannot be cast in or out of combat.
Ex. A player decides to sacrifice a "Befoul" spell with a mana cost of 2C2B. (2 colorless, and 2 black). The "Befoul" spell card is exiled from the players library for the remainder of the game session and 2 black mana and 2 colorless mana are added to the player's Mana Pool.
Any spell card that is labled as a Sorcery or Instant and grants a player life may be cast outside of combat by using an amount of mana equal to the spell's mana cost. Enchantment and Artifact spells may not be cast outside of combat. The amount of life the card allows may be added to the player's life points. A player can never exceed their maximum life points this way outside of combat. Any confusion or dispute of the effects of a card can be looked up in the MtG:RPG wiki Card Rulings . If not avaliable, the ruling will be made at the GM's discretion.