When you cast a creature spell, you are never required to choose targets for it, because creature spells never target anything. Some creatures have enters-the-battlefield (“ETB”) abilities that require targets, and you must choose one only when the creature hits the board (even if the only legal target is your own permanent that you’d rather not target).

For example, if you have a Viridian Corrupter in hand but there are no artifacts in play, you can still cast it. When it hits the board, its ETB ability will simply be removed from the stack because there are no legal targets for it. On the other hand, if you are the only player with an artifact, you must target and destroy it with the Corrupter’s ETB ability (so you probably want to avoid casting the Corrupter at all in that situation).

Keep in mind that sometimes creatures are legal targets for their own ETB abilities. You might not want to cast a turn 1 Forge Devil if there are no other creatures on the board, and similarly, Skinrender is not that good if it enters an otherwise empty battlefield.

Today’s Rules Tip written by
Jorge Pinto, Level 1 judge from Santiago, Chile