Boomsday Even Shaman ft Arcane Dynamo

Main Boomsday inclusion is adding Arcane Dynamo to discover key spells. There are only 5 shaman spells in standard with a mana cost of 5 or more, two of which are Bloodlust and The Storm Bringer, both of which we would want to run in even shaman but can't. This means you have a 90% chance to hit one of them each time you play Arcane Dynamo (or 60% chance to hit either one you are going for).

The other Boomsday inclusion is Menacing Nimbus which is a reasonable two drop elemental which provides more elementals for your Earthen Might and should help you curve out more consistently.

Other possible inclusions currently run in even shaman are a 2nd Sea Giant, The Lich King, Hagatha.