Elemental Galaxy Mage

This deck aims to control the early game by utilizing Elemental synergy, Doomsayers, Voodoo Dolls, and potentially early Mountain Giants before getting down Galaxy and proceeding to repeatedly swarm the board with big threats using draw from Stargazer Luna, Book of Specters, and Arugal.

Some notes on inclusions:

• Arcane Tyrant - helps make the Galaxy turn less of a tempo loss while simultaneously maintaining the elemental activation condition.
• Frost Lich Jaina - the ability to recover from early beatings once you have a full board is often game deciding.
• Raven Familiar - increasing the odds of a turn 6 or 7 Galaxy is too good to pass up, and sometimes it nets you a free Book of Specters anyway.
• Mountain Giant - If you have this early, it's usually worth spending Book of Specters to get out a turn 3 or 4 threat, even if it means taking a chance on burning Galaxy. The deck can easily win without Galaxy if you get this early tempo.
• Lich King - A really solid body/effect to get for 1 mana. Can be replaced with Ragnaros in a Wild version.

Notable exclusions:

• Aluneth - I've tried it a lot, as it looks tempting at first glance, but it has quite a few issues. It's another dead turn, it ruins a Stargazer chain, the fatigue often loses you easily winnable games, and it's generally just way more than is necessary (especially with Arugal).
• Servant of Kalimos - you don't need the extra value at all, and it's too slow to hold the early game.
• Pyros - See above.
• Ruby Spellstone - not worth polluting your Raven/Specters draws.
• Grand Archivist - The deck isn't completely reliant on Galaxy to win, so this is overkill in my opinion. Also, having Archivist cast Book before Galaxy is super mediocre.

Getting a turn where you chain Stargazer Luna to fill the board + dig for Jaina is very powerful, and you should try to hold onto her if possible. Arugal is not nearly as critical, and can be dumped early if convenient. Try to plan for dropping Doomsayer the turn before Galaxy if you can afford to (especially on an empty board). The relieved pressure is invaluable.

In the later game, hold onto Fire Fly rather than throwing it out willy-nilly. The flame token is added as the right-most card, so it can sometimes be a key mulligan when chaining Stargazer to avoid having Jaina or a Doomsayer stop you in your tracks. Same goes for the Flame Geysers generated by Steam Surger.

- Update -

After playing with it some more, I'd also recommend trying a version that replaces the Ravens with Grand Archivists, and Arcane Tyrants with Meteorologists. In the mid game, Meteorologist can be great at keeping the enemy board under control - but where it really shines is in the late game when chaining Luna. If their board is empty, it can often essentially be two 1-mana Pyroblasts. The extra reach is really helpful.

Without the Tyrants, the Archivist is a better method of getting out the spell, and I've come to appreciate that it's a guaranteed draw/cast.