Kobolds and Catacombs Guide
I don’t see here a too powerful win condition :/
I would assume the Win Condition is to make 4 Snowfury Giants, Thing from Below. or Corridor Creeper for 7 Mana off of Lesser Sapphire Spellstone. Add Ancestral Spirit for extra spice.
You also have 6 good board clears (8 if you count Devolve, lots of solid taunts, and solid healing from Healing Rain.
I've been playing around with a list kinda similar to this without the spellstones and with Faceless Manipulator. It does okay, but my list needed more healing - I like the Healing Rain inclusion.