Garrus Vikarian is one of the most popular party members in Mass Effect. Partway through Mass Effect 2, Shepard can help Garrus kill a treacherous former teammate known as Sidonis. This event is a significant step in his character development, and some players might not know whether to help or hinder his quest for revenge. This guide will cover a few things players might want to know before making that choice in Mass Effect 2 and Mass Effect: Legendary Edition.

The decision takes place during Garrus’ Loyalty Mission, “Eye for an Eye.” Completing the mission secures his loyalty regardless of the outcome. The mission also unlocks his Armor Piercing Ammo ability irrespective of the result. So those are two things that players don’t need to factor into their decision.

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Like most choices in Mass Effect 2, Shepard will gain Paragon or Renegade points from their decision. As one would expect, helping kill Sidonis is a Renegade action, while sparing him is a Paragon one. So, if the player is going for a 100% Paragon/Renegade playthrough or is trying to build up enough score to pass a difficult Reputation check later, that is something to keep in mind.

Meanwhile, the mission plays a vital role in Garrus’ trilogy-long character arc. In the first Mass Effect, Garrus expresses a very cavalier attitude towards enforcing the law. In many ways, he’s the archetypical cowboy cop who sees rules as just getting in the way. Commander Shepard can encourage or discourage that attitude in both games. The loss of his squad between games pushes Garrus in an even more extreme direction. Other returning characters, such as the Normandy’s pilot, Joker, will comment on his changing attitude. It comes to a head during the mission, where it’s easy to see that Garrus’ anger is getting the better of him.

Granted, he has a good reason to be angry. Garrus’ team died between games because Sidonis betrayed them to the Blue Sun’s mercenaries. But if Shepard chooses to speak with Sidonis, they learn some important details that might have influenced their decision. It turns out that the Blue Suns forced Sidonis to betray Garrus after capturing him on Omega. He’s also racked with guilt over his actions and surrenders to C-Sec if Shepard lets him go. Either way, he doesn’t show up in Mass Effect 3.

At the end of the mission, Shepard has a conversation with Garrus about its outcome. If Shepard convinced Garrus not to kill Sidonis, Garrus acknowledges there was still some good left in his former teammate. He then comments on how not everything is black and white and arguably comes away with a healthier mindset. The follow-up conversation on the Normandy stays the same regardless. Overall, the effects of the decision is insignificant outside of roleplaying. So really, the main factor is how the player wants Garrus’ story to play out in Mass Effect 2.

Mass Effect 2 is available on PC, PS3, PS4, and Xbox 360, and Xbox One. It’s included in the Mass Effect: Legendary Edition available on PC, PS4, and Xbox One.

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