Like most Magic: The Gathering cards, the value of Aven Interrupter depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Outlaws of Thunder Junction)
In the meantime, you can still pre-order booster boxes here with us
Some players, especially competitive players, don't like having to remember the differences between the Standard and rebalanced Alchemy versions of these cards
The creature must then be sacrificed at the end of the turn, though, so it isn't without a price
Spells and abilities that were targeting that permanent, as well as Auras and Equipment that were attached to the permanent, aren't affected unless the new characteristics of the object change the legality of those targets or attachments
Lets dive into the history behind these designs and see if we can learn something about how to build transforming decks in the process