MArcomage

I think this card is quite a bit too expensive for what it does. I haven't seen anyone use it in a long, long time. I think of one facility being worth about 10 resources (since cards that add or reduce a facility tend to cost 9-12 resources). Generally one gets a sort of "bulk discount" for higher-cost cards (Curse = 7.5 per facility, Gateway = 5 per facility), so I think this card shouldn't cost any more than 20 resources total.

Maybe make it 12/6?

Kidnap has the combined effects of Lightning strike & Legendary smith or blacksmith.
Not taking in account that this card saves you a turn and lacks Destruction keyword, the card should cost 11G 10R or 17G 6R
12G 6R feels too cheap, but I agree it wouldn't be a bad idea to lower it's cost.

With same reasoning:
Treacherous artifact

(Also about the reasoning: Destroying facilitys is worth slightly more then gaining them.)