The last time I talked about Mass Effect I ended up off on a tangent about how you need to play through the series from the beginning. Because it’s true. But what I meant to do was compile a list of things that I loved about the game.

As it turns out that, I was too lazy to actually record them as I played (aside from the infrequent Tweet), so instead here is a haphazard-but-not-as-comprehensive-as-I’d-like list of things that are great about the series:

Environment

I’ve spent plenty of time talking about how the environment is as much of a character as anyone else in the Grand Theft Auto series. The same is true for Mass Effect; to the point where it’s at the very least on the same level as GTA. As you explore in either game, you’ll overhear conversations between other characters and be exposed to various forms of media. And in both cases, that media is extremely well-written and enjoyable to listen to, and often deals directly with the plot that you are involved in.

Mass Effect 2 continues the tradition of acquiring side missions by observing your environment, whether that be by hacking a computer terminal, talking to a bystander, or simply by picking up an item that you have to find a use for. A few times the latter resulted in me finishing a side mission that I didn’t even realize was happening, and that kind of simple entertainment can be a welcome diversion from the core story.

Experimentation

I mentioned previously that the game keeps a running tally of the decisions you’ve made throughout the series, which results in some really surprising and well-executed events in ME2 that you’d likely miss completely if you skipped the first game, and it enforces their assertion that the decisions you make may come back to help or hinder you later.

And while it’s great to see those decisions persist throughout the series, it’s likely you’ll want to approach the story in a few different ways, especially given the breadth of things you didn’t experience if you only played through once. Thankfully, the games welcome multiple playthroughs, whether you choose to replay the story with your now-leveled-up character or start fresh. They even go as far as to separate your save files for each character (so no accidentally overwriting Character 1′s file with your progress in Character 2).

Exploration

In a universe as deep as Mass Effect‘s, it only makes sense that the player be provided with some sort of guide to it all, hence the codex. Accessible from the pause menu of both games, the codex functions as a portable, built-in encyclopedia. The depth of knowledge and the work that went into creating and compiling this information is simply astounding as it references nearly every race and creature you’ll come across in your travels, providing you with information on biology, demeanor, culture, and other pertinent details. But it doesn’t end there; the codex serves as a reference for everything from space combat to galactic history. In short, the codex is the embodiment of everything there is to love about the series.