I had a question about the extra gold you have to pay if you play multi color:
The catch is that if your heroes are more than one color, the first tech building or add-on you build costs 1 extra gold. (Neutral heroes from the starter set don’t count as being a color, so you won’t pay the extra gold with a team of red / red / neutral but you would with red / red / green.)
The total tech/add-on building cost of playing multi color for the entire game is one gold. (I.e., not one gold for each tech building / add on or anything like that.). Also, it doesn't matter if you play 2 color or 3 color, it's still just one gold extra.
I only ask because one gold does not seem like much. While the rule seems very straightforward, I wanted to make sure I didn't misread it.