Mass Effect: Legendary Edition is finally here, and with the revival of Shepard's story comes the return of some of the toughest choices in any BioWare series. From picking which team member to leave behind on Virmire to sacrificing Mordin Solus to cure the genophage, the original trilogy is packed to the brim with moral dilemmas.

There is no dilemma in Mass Effect: Legendary Edition that is a better moral litmus test than the question of whether or not to kill the Rachni Queen on Noveria. Especially as some fans are now aware of the consequences, as they were not when ME1 first released, it's a truly hard moral decision.

RELATED: Mass Effect: All Keeper Locations (Scan the Keepers)

Mass Effect's Rachni Wars

Entry 8 - Krogan Rebellions Start

The Rachni Wars are one of the most important parts of the Mass Effect lore, and were the single biggest threat to the galaxy until the re-emergence of the Reapers. The conflict began well before humanity's introduction to the galactic community, kicking off around 1 CE when Salarian scientists acting on behalf of the Citadel Council reactivated a dormant Mass Relay. Unbeknownst to the Citadel, the Mass Relay led to Rachni space. The scientists were quickly captured and experimented on by the insectoid race, and it wasn't long before the Rachni had reverse engineered the technology necessary to begin using their Mass Relay to launch an assault on the rest of the Milky Way.

The Rachni were a huge threat because of their hivemind and their numbers, which seemed endless. No matter how many Rachni were killed and how many of the Citadel's forces were destroyed, the insects just kept coming. A solution would not present itself for three-hundred years, when the Salarians uplifted the Krogan from their war-torn home-world, Tuchanka.

The Krogan had an incredibly fast reproductive cycle. Paired with their huge frames, natural plated armor, and utter fearlessness this made the Krogan the perfect weapon to take down the Rachni once and for all. They launched assault after assault on the Rachni, eventually chasing them back through the Mass Relay all the way to their homeworld, which was bombed to oblivion and back to make sure the Rachni would never threaten the galaxy again. The Krogan themselves then became seen as the next big threat, eventually leading to the creation of the genophage to slow their reproductive cycle to a snail's pace and halt the growing Krogan rebellion.

RELATED: Mass Effect Legendary Edition Trophy List

Mass Effect 1's Rachni Queen

Rachni Queen mass effect

In Mass Effect 1, centuries after the end of the Rachni Wars, Shepard and their team discover that one Rachni vessel escaped the slaughter. The ship preserved several eggs in cryostasis. One of these eggs is discovered by Binary Helix, a leading biotech and genetic engineering corporation. Finding a Rachni Queen inside the egg, the company attempted to use her to create Rachni soldiers while separating them from their queen in order to control them directly. However, it turns out that separating the Rachni from their mother makes them totally uncontrollable, leading to a break-out that killed many of the scientists.

When Commander Shepard finally confronts the Rachni Queen she possesses the dead body of Asari matriarch and Liara's mother Matriarch Benezia. The Rachni Queen asks that Shepard free her, claiming that the Rachni of the Rachni Wars were heavily influences by a "sour yellow note" that "hushed one voice after another." This could mean that the Rachni were being influenced by the Reapers, but the game never makes it explicit. Shepard can choose between freeing the queen or activating the lab's acid tanks and ending the Rachni race forever.

Mass Effect 3: The Consequences of the Rachni Queen Choice

rachni queen mass effect 3

The Rachni Queen faces players with of the best moral choices presented in the entire original trilogy, and there are many different factors at play that the player has to consider. For a start, the Rachni Wars make it clear that the species poses a huge potential threat to the other races of the galaxy. Not only that, but with the Krogan genophage in full effect in Mass Effect 1 there's no weapon to stop a new generation of Rachni from being victorious the second time around.

However, not only is the Rachni Queen clearly a being capable of feeling and empathy, she is likely the last of her kind. To make matters more complicated, she is a survivor of the Rachni Wars, but never actually participated in it. The question can be reduced to this: it is morally justifiable to kill an innocent person because of the potential threat that person may one day pose?

The decision has complicated consequences across the entire trilogy. If Shepard shows the Rachni Queen mercy, reports surface during Mass Effect 2 that claim that ships with Rachni designs have been spotted in Citadel space. The Rachni Queen promises to help "against the coming darkness" when contacting Shepard through a proxy on Illium, but in Mass Effect 3 she is captured by the Reapers and her young are transformed into Ravagers.

Although the Rachni Queen can be freed again it comes at the cost of many Krogan lives, showing that good does not always beget good in the galaxy of Mass Effect. While many Mass Effect choices see the paragon option lead to better outcomes, that is not necessarily the case with the Rachni Queen. Even against her intention, she does turn out to be a threat to the people of the galaxy.

This isolates the original decision in Mass Effect - the question becomes one of principles versus consequences. Is it better to free the Rachni Queen to avoid killing an innocent, even if that decision leads to more deaths in the future? Is it better to be willing to kill one innocent to save the lives of many more, and if so, where does one draw the line?

Not only is the Rachni Queen among the most interesting non-companion characters players will get to meet again in Mass Effect: Legendary Edition, but she also shows the game's choices at their best. The Rachni Queen decision is a moral dilemma with galactic-scale consequences across the entire original trilogy. Both options lead to certain deaths, and both save lives. Fans can only hope future Mass Effect games give players decisions with the same nuance and long-lasting impact.

Mass Effect: Legendary Edition is available now for PC, PS4, and Xbox One.

MORE: Mass Effect Voice Actors Are Holding a Reunion