One of the big selling points for the Mass Effect series is that choices made in earlier games can impact things throughout the entire trilogy. Now that Mass Effect: Legendary Edition is out, fans of the series can play all three of the games back to back and really see which choices have long-lasting effects. One path weaves through Mass Effect 1, 2, and 3 and is the difference between saving Mordin Solus' life or letting him die in Mass Effect 3.
First introduced in Mass Effect 2 as a party member, Mordin Solus is a Salarian scientist who specializes in genetics. He plays a major part in the creation and modification of the genophage, a bioweapon that is meant to drastically decrease the birthrate of Krogans. Despite not coming to the series until midway through Mass Effect 2, Commander Shepard begins impacting Mordin's storyline in Mass Effect 1. For those who just picked up Mass Effect: Legendary Edition, be warned, saving Mordin requires a renegade playthrough.
This article contains spoilers for Mass Effect 1, 2 and 3.
Saving Mordin in Mass Effect 3
Because of the many branching paths throughout the entire Mass Effect series, it's tricky to know if certain small decisions made in earlier games will drastically affect outcomes later on. For example, Wrex doesn't necessarily need to die in Mass Effect 1 for Mordin to live in Mass Effect 3, but his death certainly makes things easier. If he doesn't die early on, it's likely that both Wrex and Mordin will die during the mission Priority: Tuchanka in Mass Effect 3. Making the renegade choice to kill Wrex in Mass Effect 1 completes the first step to save Mordin later on.
Mordin's loyalty mission in Mass Effect 2 plays a big part in the overarching genophage storyline. The mission, Mordin: Old Blood, culminates in a confrontation between Mordin and his former pupil, Maelon. At the end of the scene, Shepard has a few options for what to do with Maelon's data. To keep Mordin alive in Mass Effect 3, the data needs to be destroyed which will ultimately also kill Eve, the only surviving Krogan from Maelon's attempts to cure the genophage.
Finally, if Mordin survives until Mass Effect 3, Shepard will need to be careful about what they tell their team on the way to the mission Priority: Tuchanka. Before the mission, Shepard will be contacted by Dalatrass asking them to sabotage the distribution of the genophage cure in exchange for Salarian help in the game's final battle.
To save Mordin, don't tell anyone about sabotage plans. After fighting through the mission, Mordin will tell Shepard that Eve is dead and that he needs to go up to the top of the shroud to help. If Shepard has a high enough renegade bar, they'll be able to convince Mordin to wait on curing the genophage saving his life in the process.
Mass Effect: Legendary Edition is available now for PC, PS4, and Xbox One.