Legendary Planeswalker — Teferi
Each opponent can cast spells only any time they could cast a sorcery.
+1 : Until your next turn, you may cast sorcery spells as though they had flash.
−3 : Return up to one target artifact, creature, or enchantment to its owner's hand. Draw a card.
You may activate Teferi's last ability without choosing any target. You'll just draw a card. However, if you do choose a target and the target permanent is an illegal target by the time Teferi's last ability tries to resolve, the ability doesn't resolve. You don't draw a card.