This results in a near infinite energy cycle to attach and discard throughout the game
When an MTG Battle card is played, its controller chooses a player to be its protector (there are restrictions on this depending on the Battle type)
Facilier Charletan, Horace No-Good Scoundrel, Jasmine Disguised, Elsa Ice Surfer, and Simba Future King Uncommons: Dragon Fire, Smash, and Prince Phillip Dragon Slayer Rare or above: Dr
This is also what makes the format pretty expensive to get into
Banding - Here is another ability that isn't inherantly bad, it's just needless complicated
Investment : Some Shiny cards, particularly older ones or those in perfect condition, can fetch high prices in the collector market