Rare cards:
All-elemental Attack - perhaps a 20 Resources cost would be better for this card?
Demolition Troop - just one question: When does the -1 enemy Facilities resolve? After the - Wall effect or before it?
Stonehenge - nice update.
Tubular Bells - I really like this update - it looks very well thought out. I hope it comes to use in real battles.
Catastrophe - yes, it's Rare, but there are games when you just receive a given Rare card and if it's this one, that will be the end of your opponent. My suggestion is to raise the cost to at least 30 Gems?
Word of Power - really good update - this card was semi-useless (to me at least).
Avalanche - seems good enough to give it a shot with an aggressive deck.
Tornado - I'd say that a cost of 27 Gems (along with a hidden cost of Stock: -3) would be better for this card.
Return to the begining - I'm OK with the + Wall effect, but at least a cost of 5 Resources would be better than 0 cost.
Residence of the Gods - may be the cost can be lowered to 45 Stock to make more attractive.