As Specialists lets you choose a creature type, it is just efficient in general and fits decks that focus on Zombies, Demons, Humans, Angels, Clerics, and many others
No player will get priority in between the creature entering the battlefield and being sacrificed
To heal damage from a permanent, remove all damage currently marked on it
It's where you land after you've built all the Constructed decks you want to or when your life has changed to be less accommodating to playing a ton of Magic , like when you get a full-time job, have children, etc
Among the icons in the upper right part of the screen is a lotus icon that you can click on to open up the Wildcards screen
However, if you dont intend on buying a sea of Emerging Powers boosters (I dont blame you if you dont), its much more economic to obtain the codes on their own