“You can include POST-A-TRON in your starting gang. If you do, you must invent it after shuffling your deck, waiving the ghost rock cost of inventing. Discard POST-A-TRON if you fail to, or cannot, invent it.”
“waiving the ghost rock cost of inventing” just means that you don’t pay the cost twice?
Must the inventing Mad Scientist boot to invent Post-a-Tron in the starting posse?
I’ve read on another topic that it’s possible to use Morgan Gadgetorium while inventing Post-a-tron, is it also possible to use Prof Aloysius Roe’s react ability?
Yes. Inventing rules have been a little cleaned up since then, but it’s just making sure you don’t pay twice since technically, you would pay to put him in your starting posse, then follow invention rules which also tell you to pay the ghost rock.