Very cool. I used to love Atiesh and the way it could make even slow decks have some tempo. However, this version looks viable for all kinds of shaman decks (except aggro maybe)
I don't know if the bodys of the legendary minions pool is at least avarage, but I really like this card. If you are in a non weapon meta, you can play this on curve and you can enjoy good tempo plays next turns or you can play later using spells in the same turn and if you summon a single 4/5 the card already paid its cost using only one durability.
The most value minion cost is 6 (8 low roll is a 1/1 while a high roll is a 12 12, 7 low roll is a 2/4, 9 low roll is a 5/5, 6 is a 3/4). Also with 6, you can either do Rain of Toads, Eureka! or The Storm Bringer, which is good value.
5 slot is pretty variable. I counted 17 in the game right now. Low rolls include Duskfallen Aviana (!!!), Gral the Shark, and Haleezi The Lynx. 4 out of 17 bad ones so around 25% you are unhappy. High rolls off Hagathas Scheme include Leeroy, Zilliax, and Darius Crowley (good for sticky minions).
7 slot seems to have 24 legendaries and is less high rolly. 6 of the 24 are below a 5/5 statline so 1 out of 4 Earthquakes will give you garbage afterward. 2 are 5/5s. High rolls are Velen, Antonidas, Rafaam and Goru the Mighttree.
To much variance. I love the idea behind the card however. It makes it possible to create new archetypes. Blizzard needs to keep ideas like these coming. This card isn't a meta breaker or anything, but at least it is something different without just being power creep.