If a later part of a spell applies a Replacement Effect that alters earlier parts of the spell, apply those replacement effects as appropriate. Example: A spell says "Choose a unit. Kill it the next time it takes damage this turn." and "[Legion] — Kill it now instead. (Get the effect if you've played another card this turn.)" If the Legion condition is satisfied, the unit is killed immediately and the instruction to kill it the next time it takes damage is ignored, even if the unit remains on the board somehow. See rule 367. Replacement Effects for more information.
§ 158.2 Core Rules PDF (officieel)
§ 158 When a spell is successfully played, a player executes the rules text of the spell. This is called Resolving the spell.
