Awesome / Space Engineers

• Like any construction-centric game: Putting the finishing touches on a particularly large and complex ship, and then taking it out for a test-drive.
• The destruction physics are a joy to behold. Crash two Large Ships into each-other, and watch their hulls warp and deform as they slowly crunch together into a barely-recognizable mess.
• In multiplayer, fights between the nimble Small Ships involve lots of Old-School Dogfighting - requiring skill in the pilot's seat as well as effective design in your own fighter. That moment when you realize you've just destroyed your opponent's cockpit, main engines or power generator; disabling their ship and leaving them dead in the void; is a moment of victory.
• Since the physics in the game are relatively accurate, not only are you Old-School Dogfighting, you're dogfighting using real space physics. If you ever wanted to know what it'd be like to fly a Starfury or a Viper...
• In regards to the game's modding community: As of Update 01.048, alongside reloadable rocket launchers and modding API, KEEN Software House announced that the popular Fighter Cockpit mod, created by Steam user 'Darth Biomech', would be integrated as an official part of the core game. They've since gone on to implement several more popular mods this way.
• The long-awaited release of Planets. The planets in question are Baby Planets roughly fifty kilometers in surface size, meaning a hundred players could be on a single world and would barely see each-other. There are three different types of planets (Habitable, Barren and Alien) complete with sizable moons, and the distances between them are vast compared to everything that came beforehand. The 100 meter-per-second speed cap is suddenly a snail's pace.