I was 10 hours into Civilization VI before I remembered I wasn’t even playing the full game.

My preview build didn’t have as many civilizations as the full game will when it launches on October 21. There weren’t as many game set-up options and only one difficulty, the baseline Prince. But there was no turn or time limit, and that’s all I needed.

Sid Meier’s Civilization VI, the latest in a landmark strategy series that spans decades, is less a game of sweeping changes than it is minor tweaks—and that’s a good thing. Civ V, released a lifetime ago (in video game turns) back in 2010, was damn close to perfection and kept gamers—this one included—coming back for hundreds and hundreds of hours. Messing with that formula too much might have been a recipe for disaster. Instead, Firaxis kept what worked and enhanced everything along the way.

In my first game, I didn’t go to war with anyone. I’m a sucker for a good military victory, but I was too busy trying to get a handle on the new city-building elements to grow a fearsome army. I was Theodore Roosevelt, Team USA, founding familiar cities like New York and Washington in a new world. Instead of all buildings and wonders living in one tile, players can now build up districts throughout their borders to rack up culture, science, gold, faith, and general happiness. This is the biggest change from Civ V to VI—city planning isn’t as easy as plopping down farms and mines wherever happens to be convenient. That means tile space is more in demand than ever, forcing the player to really think about what’s being placed where.

Districts are probably the biggest change, or at least the biggest change that I noticed in my dozen or so hours, but there are plenty of small tweaks. For example, instead of workers, Civ VI utilizes builders; they can improve tiles in a single turn, but disappear after three improvements, so use them wisely. Certain actions can bank points toward science goals, cutting the number of turns it takes to research them in half. This is great because it adds even more indirect directives and works a subtle layer of strategy into the science tree. Non-fighting units can be linked with combat escort units; most of us were already using fighters to accompany helpless units like settlers, so that’s a natural move. Oh, and on top of providing enough food for each city, you’ll also have to make sure your citizens have enough housing.

Elements that weren’t included in Civilization V until its expansions, namely religion and espionage, are in vanilla Civ VI, which means even more elements to manage. One of the ways to win is with a religious victory, but if religion’s not your favorite strategy, you don’t need to go that way—just don’t be surprised when religion from other countries starts spreading to your cities.

By the time I founded Philadelphia, I was feeling pretty good in Teddy Roosevelt’s shoes. Washington and New York were thriving, the army was good enough to defend any wayward invasion, and I was getting a grip of Civ VI’s intricacies. However, I didn’t keep a close enough eye on the other three civs on the map, and promptly lost the game without warning. Since victory cinematics are under wraps until the full game, I’m not even quite sure how, but I spent little time lamenting my loss before starting over again, clicking through a hundred turns and then 200. This time, I embodied the Roman Empire, with a fearsome military and sprawling cities spanning the map.

Teddy didn’t like this.

He declared war within 50 turns, which caught me by surprise since I hadn’t gone to war at all in my first playthrough. I was ready for him, though, and found battle largely the same as in previous Civ games. There’s a more in-depth upgrade tree for each unit, but other than that, it’s quite familiar; my strategy is always using a mix of melee and ranged fighters to clear out invading forces before going on offense. Teddy backed down after I took Baltimore, and I accepted the terms of his surrender since they involved lots of rewards for me.

After a dozen hours, I’m more than ready to see what the full Civilization VI experience is all about. So far, I’m in love. I played Civ V for 300 hours over several years, and no game since has had that kind of hold on me; its sequel is certainly going to try.

Civilization VI will be out on Oct. 21 for PC.