These allow you to play "tall," expanding your population by building orbital space stations instead of colonizing new planets.
If you don't want to wait until May 11 for the free update, you can find deals at retailers like dLcompare or Play-Asia for significantly less than the $19.99 Steam base price. Stellaris Utopia Review
Reviews consistently rate Utopia as the most important expansion for Stellaris because it fundamentally changes how you play the mid-to-late game.
You can build massive engineering marvels like Dyson Spheres (to power your empire) and Ring Worlds .
You can play as a single unified consciousness, completely removing internal political strife but changing how you interact with other species. Where to Get It