Coupled with Sundial, it's way too powerful for its card space.
What about weakening it, like "Delay enemy creatures equal to the number of cards in your hand for 1 turn. Removes invisibility."
Otherwise, you could add in a weakness, like making it a permanent, or adding the effect "Undelay an enemy creature for each card your opponent plays."
It's not that UP for things with more than 3 HP...