by thanos2001
I went to the source forum and got an answer. I was way off. So happy to have this resolved!Here is the example provided for an enemy mage attacking a mage with Reverse Magic already attached:
1. The enemy mage pays 2 mana and casts Force Hold face down.
2. You reveal Reverse Magic, pay 5 mana, and then gain control of Force Hold.
3. You attach Force Hold on the enemy Mage. This does not cost you any mana, the casting cost has already been paid by your opponent.
4. You can now flip and reveal Force Hold, if you wish, which costs you another 2 mana.
Reverse Magic is pricey when working against enchantments. In some cases, stopping and reversing their action is a terrible surprise that is worth that cost. You can, of course, choose to not pay the reveal cost when it is revealed, which will just cancel and destroy Reverse Magic without effect.
Reverse Magic is particularly effective against incantations.
Reverse attack can be expensive, especially if attacked by a weak attack. However, reversing an 8 mana Fireball is awesome!