Change of Fortune is a new archetype-defining card for protection! A 1-cost upgrade with the potential to generate 2 resources every turn is unheard of even for an identity-specific card, not to mention an aspect card. It is, of course, restricted by how often you can actually defeat an enemy during the villain phase. There are plenty of player cards to do this...the bigger question is will you always have an enemy to defeat. Once a game you can defeat a villain stage, but this card will heavily depend on the number of minions you draw.
Powerful Punch is my favorite option for defeating a minion. It deals a big chunk of damage and counts as defending, allowing you to trigger various Unflappable effects. Counter-Punch and the new Under Control have better damage per cost but require you to defend. Energy Barrier also works really well. You can trigger it during the villain attack to finish off a minion before it even activates against you. I do like the proactiveness of Under Control and Energy Barrier, as it can be risky to hope you draw a damaging event going into the villain phase (assuming you use your whole hand on your turn, as should usually happen)
Many heroes have identity-specific cards that can take advantage of Change of Fortune. Ghost-Spider has Ghost Kick for a huge chunk of damage. Nightcrawler has Tally Ho!, Gamora has Crosscounter, Nova has Forcefield Projection, Magik has Magic Barrier, and there are a few others. I also want to highlight Thor and Valkyrie, who each have a card that ensure a minion will be in play in Defender of the Nine Realms and Chooser of the Slain. These decks would also benefit from a "Come Get Me, Bub!". Indeed, while there are tons of protection cards that can damage in the villain phase, I believe having a minion in play will be the greatest obstacle to this strategy. For that reason, the strategy definitely improves with higher player counts.
Here are some cool decks from marvelcdb that you could take for a spin to try out this new card:
- This highly upvoted Psylocke deck by journeyman2 uses Psychic Misdirection as its minion-killer...a very powerful card available only to a few heroes due to the Psionic requirement
- Castlefrank47's Black Panther deck takes advantage of his inherent retaliate, but also uses Nova and Warpath to enable kills in the villain phase...very cool.
- And lastly, one of my favorite decks I've ever played, which I used to beat the Sinister Six on Heroic difficulty with Ghost-Spider. This scenario is highly exploitable for Change of Fortune due to the multiple villains, but I think the deck still stands on its own.