Classic big spell mage, but added Luna's Pocket Galaxy, and some minions wich synergy with it. Against aggro you most of the time wont play luna’s pocket galaxy, but vs control playing it as soon as posible may be match defining.
Archmage Arugal can be played at tempo in fast matches, but its power is meant to combo with Luna's Pocket Galaxy and/or your draw cards.
Bright-Eyed Scout is always an useful card, as more than half of your deck is 5+ mana cost, and you will mostly mulligan for low costs. Isnt actually that bad if played after Luna's Pocket Galaxy. Witchwood Piper when played after Luna's Pocket Galaxy will draw any minion from your deck.
Arcane Dynamo is a card very fitting for big spell mage, as it can provide an extra AoE or a Pyroblast to close a game. It synergises with Dragon caller alanna, but also has a very powerful synergy with Luna's Pocket Galaxy when you play it for 1 mana, giving you the chance to play the discovered spell right after. Astromancer synergises with the heavy hand style of the deck.