Mulligans
General Mulligans
These cards make for a good early board, which should be good in most matchups.
Primordial Glyph is always good to keep, because you can make some good power turn where you play for example a discovered firelands portal in turn 5, but it also helps you to deal with a variety of situations
Aggro Mulligans
These cards are good to get an early board that you will need against aggro decks
Midrange Mulligans
Polymorph is good for cards like Savannah highmane, if you cant think of any good targets to polymorph then dont keep it.
Combo Mulligans
You want to play medivh on turn 8 if possible get much value in the follwing turns before the enemy gets to do his combo.
Don´t keep Medivh if the enemy is likely to have a dirty rat.
Control Mulligans
Good cards to get some kind of boards while also keeping a full hand
This is a very good Control mage deck invented by Psygünter.
He and Dog had really good success with this list on legend ladder.
Is there any replacement for alexstrasza and bloodmage thalnos? Can craft everything, but not legendary (I have used all my dust on Antonidas and Mage quest).