I have Rocket Backpacks giving the first minion I play Rush, and Special Delivery copying that minion (with 1 health).
However when i play Escaped Manasaber, a copy is not created even though it does get Rush.
ALSO, If I use Invigorating Blossom (Hero Power) before playing the minion whose cost was reduced, it will be granted Rush, but no copy will be created.