Mass Effect 3: Citadel offers a galaxy of choices

It's the ultimate gift to long-patient fans, but Mass Effect 3 Citadel's also the most technically ambitious module of BioWare's much-praised divergent narrative system. Brenna Hillier reports.

Some spoilers ahead but seriously, come on guys - Mass Effect 3 came out in March 2012.

Mass Effect 3: Citadel is the final piece of DLC the trilogy will receive, and although it takes place before the end of the third game, it's probably the last Commander Shepard adventure many of us will ever play. It's not just that it released a full year after Mass Effect 3, it's that it quite deliberately sets out to give us what we wanted - a fan-service heavy chance for fans to farewell the valiant commander as she deserves.

BioWare ought to be and quite rightly is highly praised for serving up this last adventure, which sees the return of every possible cast member, and even brings back some who have passed beyond, in various respectful ways. It unites the whole crew of squadmates as we've never seen them before - one unit, fighting together - and later gives you the chance to see them at their silliest, drinking, dancing, and in more than one case, throwing up in the toilet.

Amidst all the praise and celebration, it's easy to overlook the fact that in handing over this precious gift BioWare has been extremely clever. You don't notice this as you play through Citadel, but it's one of if not the most complex modules the series has produced to date. The sheer number of possibilities the story must allow for - who's alive, who's dead, who's in bed with Shepard now, who was in bed with Shepard before, what DLC you've played, what decision you've made in each of the three games - is staggering, and unlike every other part of the game, you're given free rein to pick whoever you want in your squad almost all the way through.

That means more dialogue than any section of comparable length has had to pack in before - and it's all behind the scenes, where you're unlikely to notice it. Unless you make a couple of wildly different playthroughs (or use save manipulators) your only hope of seeing much of this content is via YouTube, where you'll uncover treasures that'll make you realise there are stories upon stories in Mass Effect you never even knew existed.

"To give you a general sense of scale, the apartment party section in The Citadel contained roughly 25% as many plot states as all of KotOR, and had more plot states than any DLC we had ever done.”

"When measuring divergent story points, there are a number of metrics that we can use, but most applicable to the game would be a data construct called a plot state," BioWare's Mike Gamble and Dusty Everman told us in an email.

"Plot states are used to record and store various bits of information about your playthrough. Whether it’s if Wrex is alive, or if you’ve gone on a second date with Liara, plot states holds a wealth of information. Because of the sheer number and depth of these plot states, speaking generally about divergent story points is somewhat difficult. That said, to give you a general sense of scale, the apartment party section in The Citadel contained roughly 25% as many plot states as all of KotOR, and had more plot states than any DLC we had ever done."

Let me repeat that for emphasis: the apartment party section. Not the whole DLC. How many is that? BioWare wouldn't say, but it did tell us that the number of plot states for the trilogy as a whole is "easily in the thousands, especially when you consider the plot state complexity has been compounded subsequently for each game and DLC".

Quite understandably, BioWare has never sat down and charted out the whole trilogy on one map. Possibly because it doesn't have a big enough conference table.

"There is no singular map that holds all of the plot states. Instead, we use our writing and level design tools to manage them. That way, they can be easily manipulated by the designers, and our tools keep track of what each plot state does," the developer said.

Watch on YouTube

Dancing with Garrus? You. Are. On.

"Of course, there are still a few senior writers and designers who have a very good understanding of the system in its entirety."

Can you imagine having all that information in your brain? You probably think you know the whole of Mass Effect pretty well, if you're a fan. You probably know most of the unique and ambient dialogue options, either from experience or from browsing fan-made compendiums like the Mass Effect Wiki. But it's almost guaranteed that there's at least one little snippet you've never heard of or seen, that would delight or amuse you.

Let's take a few examples from the beginning of Citadel, directly from BioWare:

• At the start of the DLC, the squad mate who comes to your rescue before the car lot is your ME3 love interest (i.e. Liara, Ashley, Kaidan, Garrus, or Tali), or Liara otherwise (i.e. your love interest is Miranda, Jack, Thane, Jacob , Traynor, Cortez, or you don’t have a love interest).
• If Wrex is alive, he takes out the merc shuttle. Otherwise, it’s James.
• If Traynor is the love interest, Shepard can kiss her at the Normandy airlock to prove she’s the real Shepard.
• If EDI is brought along as a squad mate when returning to the Normandy, there is humorous scene where her control and senses within the Normandy are disconnected.
• If Jack is a love interest, one of her character moments is her giving Shepard a tattoo. Otherwise, she has adopted a varren.

This is, of course, just a tiny sampling; at almost any point in Citadel - or Mass Effect in general, really - when a character speaks, who it is and what they say is determined by something you've done. For example: part way through Citadel, Shepard and two squadmates are locked in a vault. The three characters exchange a few comments, and one character is plainly more nervous than the others. But on your second playthrough, depending on who you've brought with you, the nervous character may take the other role.

"We went with an order determined by who seemed most likely to be worried or had an anxious personality, and then, failing that, by who was funniest in each role. For example, Tali will always be the worried one if she's present, and Wrex will never be the worried one," BioWare explained.

Even just this one short exchange would need to be played dozen of times in order to hear everything on offer.

In this way, players are almost guaranteed to see and hear different dialogue with every combination of squadmates they bring along; even just this one short exchange would need to be played dozen of times in order to hear everything on offer.

Few gaming franchises have captured the attention Mass Effect has over its all too brief life to date (just look at the reaction to the original ending. When was the last time you got so upset about the abrupt goodbyes of your favourite characters that you started a petition and raised significant cash for charity?) and Citadel is the perfect bit of closure to that attention. BioWare is to be applauded for its commitment to giving fans the satisfying, bittersweet farewell they wanted. But it must also be commended for pushing consequential choice in gaming to such a level that most players don't even know it's there.

Every Mass Effect 3 players' story is unique, built from the thousands of actions big and small made over the course of who knows how many tens of hours. When you explore the Citadel one last time, remember that you might be the only Shepard ever to walk that particular path.