Mordin Solus is a fictional character in BioWare's Mass Effect franchise, who serves as a party member (or "squadmate") in Mass Effect 2. Mordin returns as a supporting character in Mass Effect 3. A Salarian (one of Mass Effect's alien races) scientist who was once a member of the Salarian intelligence organization Special Tasks Group ("STG") earlier in his life, Mordin is depicted as a fast-talking and affable individual who is initially guided by scientific principles and logic, but later changes his mind and attempts to undo his earlier work. Mordin is voiced by Michael Beattie in Mass Effect 2 and William Salyers in Mass Effect 3.
Within the series' narrative, Mordin helped create and distribute measures to strengthen an artificial population control plague, named the genophage, used against the Krogan, a fast-breeding warlike alien race. Mordin is recruited in Mass Effect 2 as the Normandy's main doctor and scientist and defends his work on the genophage. He returns in Mass Effect 3, where he attempts to manufacture a cure for the genophage in response to the galaxy-wide invasion by the antagonistic Reapers and intends to distribute it in the atmosphere of Tuchanka, the Krogan home world. Mordin also makes an appearance in the ninth issue of the Mass Effect: Foundation comic series. Inspiration for his face was taken from Clint Eastwood, with developers differentiating him from other Salarians by making him older and removing one of his horns. David Kates composed his musical theme, a highly electronic piece that contains many counterpoint elements.
The character has been positively received, being nominated for three "Best New Character" awards and earning numerous placements in "top character" lists. Critics have praised his fresh interpretation on the scientist trope and his approach towards philosophy and religion. At one point in the second game, Mordin sings an alternate version of Gilbert and Sullivan's Major-General's Song, which numerous critics considered one of the trilogy's best moments. His possible sacrificial death scene has received significant commentary commending its underlying sadness and emotion. Scholars have discussed Mordin through a narratological point of view. As with other Mass Effect squadmates, merchandise for Mordin has been made, such as a bust and multiple PVC statues.