Rule 811.1.d.2.a
Each target is treated separately and individually when processing this rule. Example: Smoke and Mirrors is a spell that reads in part “Choose a unit you control and another unit you control at a different location.” If Smoke and Mirrors is played from hidden, the first unit chosen can be chosen at the battlefield Smoke and Mirrors was played from, so it must be. The second unit chosen explicitly restricts targeting in a way that makes this impossible, so it can be chosen from any location.