Bioware's smash-hit game trilogy Mass Effect thrusts the player into a 22nd-century setting where a united humanity is taking its first steps onto the galactic stage, and alien races like the Asari, Turians, Salarians, and Batarians give them a mixed reception. Humanity has to find its place in the galactic order, and soon. And Commander Shepard (with some squadmates as backup) has to face all of humanity's greatest enemies.
First, it's Saren Arterius, a rogue Spectre who falls under sway of the Reapers and assembles an army of geth and cloned Krogan to back him up. Then there is the enigmatic Illusive Man, the crafty mastermind of the pro-human Cerberus splinter group. Both of them make for compelling villains in many ways, but if they are compared, which one comes out on top as Commander Shepard's ultimate nemesis?
10 Saren: Elusive Super-Agent
Saren is a Spectre, which is saying a lot. He's not just a soldier or a cop; he's an elite operative who only answers to the Council, and he has total operational freedom out there in the field. As the Salarian councilor put it, Spectres are chosen, not trained.
This greatly flatters Saren, who must be loaded with qualifications to obtain a rank like this. And even among the illustrious Spectres, Saren ranks as the best, and he was once considered a model Spectre. Now, as a villain, Saren can use those gifts against Shepard.
9 Illusive Man: Compelling Mystery
The Dark Horse comics shed some light on the Illusive Man, such as his role in the First Contact War, but for the most part, he's shrouded in mystery. Given his methods and his leadership in Cerberus, this is totally fitting.
He was once known as Jack Harper, but is that his true name? On which planet was he born, and did he go to college? Join the military? All the player knows is his preferences for things like cigarettes and bourbon and nice suits, classic villain stuff. Otherwise, he hides it all behind a false smile.
8 Saren: Dramatic Entrance
Both Saren and the Illusive Man dominate any scene that they are in, but Saren makes a more impactful first appearance than the Illusive Man does. He first appears later in the Eden Prime mission, at the spaceport.
Nihlus, another Turian Spectre, got there first and was stunned to find Saren waiting for him. Nihlus lamented the situation and turned his back, and Saren took this chance to shoot him right in the back. Shepard can hear the gunshot's echo even before arriving at the spaceport.
7 Illusive Man: Initial Moral Ambiguity
In the events of Mass Effect 3, it's abundantly clear that the Illusive Man is a villain, and no one outside of Cerberus supports him at all. But in the second game, he's more ambiguous, and that makes him compelling in all kinds of ways.
The player is left to decide for themselves if the Illusive Man's aggressive pro-human agenda is an effective shield for humanity in a dangerous galaxy, or whether his motives are xenophobic and would make more enemies than friends on the galactic stage. Mass Effect encourages you to make decisions of all kinds.
6 Saren: Huge Army
While the Illusive Man has battalions of Cerberus soldiers under his command, Saren boasts a larger army to do his bidding. Due to his connection to Sovereign, the ultimate machine, the Geth flocked to Saren as a prophet of their god.
Both the geth and Saren were mistaken, but all the same, Saren did raise a very impressive army that was relentless, powerful, and fearless in battle. From Eden Prime to Ilos to Noveria, Commander Shepard had to face legions of these wicked machines, and don't forget the Krogan clones he grew at that Virmire lab.
5 Illusive Man: Crafty Tricks
True, Saren is also good at plotting, but the Illusive Man is the real brainiac between them. He is a brilliant man, able to personally oversee all of Cerberus' various operations, and he knows how to manipulate or use just about anyone.
That's essential for any cool villain. In Mass Effect 2, the Illusive Man lured Shepard into a seemingly abandoned Collector ship, and he uses either Kaidan or Ashley to confirm the Collectors' interest in Shepard. In Mass Effect 3, he engineered Udina's coup against the Council (which failed, fortunately).
4 Saren: Immediate Stakes
The Illusive Man goes through a slow and steady descent into madness, but right out of the gate, Saren is hell-bent on destroying the entire galaxy, the maximum stakes that Mass Effect can offer. He doesn't do things halfway.
From the start, Saren wants to bring the Reapers back, and he's ransacking the galaxy to find clues about the Protheans and the Conduit, so he unlocks the Citadel's mass relay capabilities and bring the Reapers back. The voice recording that Tali gives Shepard confirms this early in the game, adding some serious tension to the narrative.
3 Illusive Man: Resourceful
Saren was crafty enough to get the geth on his side, but the Illusive Man is a little more cunning about gathering more assets and tools for the Cerberus cause. He will get his hands on anything that can be converted into a weapon.
He found a way to build a bigger, better Normandy in secret, and later, he wanted Shepard to keep the Collector base intact so he could harvest its secrets and technology. If so, the human Reaper's remains appear in Mass Effect 3. Also, the Illusive Man is able to use quantum entanglement particles and advanced AI to better supply Shepard for the mission.
2 Saren: Change of Heart
Saren and Commander Shepard come face to face one more time in the Citadel during the Geth/Sovereign assault, and they meet in the Council chambers, symbolically enough. There, Shepard gets another chance to try and talk Saren out of all this.
Doing so requires a lot of paragon or renegade points, but if the player meets the requirements, they can convince Saren to break away from Sovereign and abort his mission. It's a remarkable scene when Saren realizes that he was wrong, and ends his own life to save the galaxy from himself.
1 Illusive Man: Breakdown
Commander Shepard comes face to face with the Illusive Man as well, and in some ways, this scene echoes Saren's from the first game. The difference is that Saren can break free of the Reapers and thank Shepard for saving him, while the Illusive Man is in anguish.
But it's interesting to see, and quite dramatic for the normally calm and cool Illusive Man. He's defensive and in denial as both Shepard and Anderson talk him down, and he realizes that he's gone too far to try and advocate humanity. He let the Reapers give humanity a false future, rather than try and craft humanity's own future. He even takes his own life out of sheer despair, especially since he can't fully break free of the Reapers. A tragic end.