A fail case is you scry 1, draw a card, and nerf an attack, which isnt bad
Just take a look at how adorable the vampire isyes, she has sharp teeth, but she looks harmless by calmly cuddling cute looking bats
It reads: As long as this spell is on the stack, players cant cast spells or activate abilities that arent mana abilities. If this was able to stop a player from morphing a creature then Sudden Shock would be a great answer to morph creatures
Fortunately, for players who do want to pull this ridiculous stunt off, a Redditor has already asked the hivemind if this was reasonably possible
"Final Fantasy 14's Naoki Yoshida on the next generation and the challenges of future-proofing MMOs"
Instead, you can choose to reveal the card and then if you do, you lose life equal to is mana value and put it in your hand