What does it mean when a card has two Faction Symbols at the top of the card to the left of the cost?

This is known as 'Steadfast'.

From the Core Rules --

Steadfast

Some cards have faction symbols in their title. These symbols are part of the card’s cost. These new cards are know as Steadfast cards. When a player drains a domain in order to pay the resource cost of playing a Steadfast card, he must have at least that many resources on the total number of domains he controls (and make a resource match as normal).

See also the example in the rulebook on page 12.

Thanks!