Riddleform
Enchantment
Whenever you cast a noncreature spell, you may have this enchantment become a 3/3 Sphinx creature with flying in addition to its other types until end of turn.
: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Steve Argyle
Core Set 2021 (M21)
• #64Rulings
Riddleform's first ability resolves before the spell that caused it to trigger but after targets for that spell are chosen. It will resolve even if that spell is countered.
(wotc • 2020-06-23)
If Riddleform becomes a creature the same turn it enters the battlefield, you can't attack with it unless it gains haste.
(wotc • 2020-06-23)
Rulings
Riddleform's first ability resolves before the spell that caused it to trigger but after targets for that spell are chosen. It will resolve even if that spell is countered.
(wotc • 2020-06-23)
If Riddleform becomes a creature the same turn it enters the battlefield, you can't attack with it unless it gains haste.
(wotc • 2020-06-23)