If I cast an instant for 1, ({Dream Twist}, for example, with {Lunar Mystic} under my control, can I activate the ability more than once? (For instance, could I pay the card cost, pay the 1 colorless 4 times, and then draw 4 cards?
The simple answer: no. It is not a reusable activated ability. It is somewhat of a triggered ability that will allow the activation once per trigger. I am no rules pro, but activated abilities usable multiple time generalls have the activation cost at the begininng, with the effect after. The format would look something like
"{U}: Draw a card." If it could ge activated indefinitely. I think... I hate being uncertain.
RESOLVED
My first official "Resolved" sticky <3