It's an equivalent exchange
In multiplayer a lot, this is very strong since you'll net multiple runs of attacks your way for each attack you can unleash so you need protection
Detective work by fan site Pokebeach suggests two of these sets may be called 'Mega Brave' and 'Mega Symphonia', based on previously registered trademarks for those titles, and the fact that those are the main attacks shown on the cards for Mega Lucario ex and Mega Gardevoir ex cards
In a regular frame, this slot has the 20 uncommons (75%), 18 rares (21.3%), and 4 mythic rares (2.3%)
Characters with Ward like Jetsam, Riffraff and Flotsam, Riffraff (if you have Jetsam in play) are particularly sticky , while Evasive characters like Don Karnage, Prince of Pirates and Wildcat, Mechanic can be hard for your opponent to remove