Marcy: Honestly this is pretty nice, three mana gets you back something at three mana and then if you're playing Legendaries, which are pretty easy these days, this could certainly get you some solid value
Keep your cards and/or binders in a climate-controlled, cool and dry environment which maintains a steady temperature year-round (this means no sheds, garages, attics or storage units!)
This bonus card is a fantastic addition for any collector
It gives all your humans two solid keywords (lifelink, first strike, or vigilance) right as it enters
If a source would deal damage to the chosen player or a permanent they control, it deals double that damage instead
In this way, similar to the Ninjutsu Commander cards, you can cancel out the increasing costs of your own leader time and time again