Mulligans
This is a tempo deck that aims to set up a lot of small minions and then combine Electra Stormsurge with Bloodlust.
Turn 1: Fire Fly is always the best play on turn 1 as it is the only 1-drop minion and will leave you with another cheap elemental token. If you have the coin you should choose to play the token immediately unless there is a specific reason to keep the elemental tag or keep the coin.
Turn 2: Earthen Might, Flametongue Totem, Menacing Nimbus, and Primalfin Totem are all valid plays, depending on the state of the game.
Mid-game: Look to set up a wide board with minions such as Saronite Chain Gang, Explodinator, Sea Giant and Fungalmancer.
Win conditions: Voltaic Burst, along with all of the damage spells (Zap!, Lightning Bolt, Lava Burst) combine with Thunderhead to set up a board. Electra Stormsurge can be combined with Bloodlust or Lava Burst as a secondary option. There is additional burst damage with Leeroy Jenkins.
Utility cards: Thrall, Deathseer and The Storm Bringer are other cards to take advantage of a wide board with cheap minions, specifically to get them to stick for an additional turn. Elementary Reaction is used for card draw. Tar Creeper is used for the elemental tag and a solid 3-drop. Spellbreaker is used for silence. Storm Chaser is used to draw Bloodlust or The Storm Bringer.