Mulligans
General Mulligans
These are the cards that you want in your starting hand the most. Crystal Power, Wrath, and Swipe allow for early removal, which is great to keep the board in your favor. Landscaping, and Dreamway Guardians allow you to get minions onto the board. Then Dendrologist can give you useful spells that can help you get out of sticky situations.
Aggro Mulligans
Healing, choose one spell generating with Stalladris, and Crystal Stag board swings will be your main keys of success against aggro decks. This is also shows the two biggest reasons I put Crystal Power in this deck. 1: the cheap cost allows for fast card generation with Stalladris, and 2: it makes for an easy and immediate activation for Crystal Stag.
Apparently the site won’t allow me to add the mulligans for combo and control, so let me know if you’re curious on how to play against those.