One of the best 4X strategy games of our generation. It provides every customization you can wish for. Stellaris has one of the best empire creation tools ever developed. You can experience brutal warfare and delightfull diplomacy. You can truly fell the RPG elements in this 4X game. You must manage the economic, political and social aspects of your empire. Furthermore, the amazing sci-fi setting provides an interesting narrative for the player to enjoy. Different pop-up events are forcing the player to deal with different highly important decisions. It really is a blessing to play.
Now to the typical Paradox DLC "Challange".
Frankly, you need to have every DLC to fully enjoy this game. Don't get me wrong you can have fun without them but they can enrich the gameplay enormous. That's why this review includes a DLC-Buylist with personal comments.
1. Utopia (Includes essential gameplay mechanics and megastructures)
2. Apocalypse (You can build your own "Death Star" which also can move)
3. Distant Stars/ Ancient Relics (Both highly improve the midgame)
4. MegaCorp (Space Capitalism = Awesome, also new empire type)
5. Leviathans (Extra early to mid game challenge)
6. Synthetic Dawn (You can play as robots)
7. All the Species DLCs

Verdict:
Definitely a must buy for all 4X strategy gamer out there. It provides awesome gameplay and nice RPG elements.
Final Score: 9.8/10 Masterpiece