The basic structure is very similar. You have starter decks of ten cards, a galaxy row of six cards to buy, and a supply of 10 outer rim pilots who are always available. The big differences are:

1. Certain cards can only be bought by one player, and the other player has to spend attack damage to kill them instead. For example, Han Solo can be bought by the alliance and added to the alliance player’s deck, or bounty hunted by the empire for a one-time reward.
2. Instead of a single life pool, you have a selection of planets to choose from, and whenever one planet is destroyed you can’t do any more damage to the opponent that turn. Each planet has a unique thematic ability: Hoth has a shield generator that blocks the first 2 damage each turn, the Death Star has a superlaser that can be activated for 4 credits to destroy an enemy capital ship (star realms base) instantly.
3. The Force. The empire goes first, but the force is with the rebels. Certain cards and bounty hunting rewards affect the force, moving it back and forth on a seven-space track. If the force marker is all the way to your side at the start of your turn, you get 1 extra credit that turn. Certain cards get bonuses if the force is on your side of the track- Vader gets +4 attack, X-wings draw a card, Death Troopers get +2 attack, Luke can instantly destroy an enemy capital ship.

All of these changes make the game significantly more asymmetric than Star Realms in which any player can buy cards of any faction, and the galaxy is utterly deprived of any force to bind its inhabitants together.