Flash Rule 702.8 Glossary

A keyword ability that lets a player play a card any time they could cast an instant. See rule 702.8, “Flash.”
Flying Rule 702.9 Glossary

A keyword ability that restricts how a creature may be blocked. See rule 702.9, “Flying.”

Rulings (1)

October 1, 2007 Wizards of the Coast
The value of X needs to be determined both when the ability triggers (so you can choose a target) and again when the ability resolves (to check if that target is still legal). If the number of Faeries you control has decreased enough in that time to make the target illegal, Spellstutter Sprite’s ability won’t resolve (and the targeted spell will resolve as normal).

Other Printings