BioWare introduced the world to its world of Mass Effect in 2007, a space opera series where Alliance hero Commander Shepard must face great alien dangers in a huge galaxy to take down Saren Arterius and prevent the return of the deadly Reapers. In the second game, Shepard enlists the aid of Kasumi Goto, and in Mass Effect 3, the last  Prothean makes an appearance.

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Kasumi Goto is a master thief who agreed to help fight in Commander Shepard's suicide mission against the Collectors, and Javik is a Prothean soldier who is sworn to fight his ancient enemies once again. Both of them are fascinating and compelling squadmates, but which one is truly the best of them all?

10 Javik: Prothean Insights

For a long time, the only evidence of the Protheans was their scattered ruins, and Liara is an expert on Prothean remains. She believed that this extinct race was a benign and wise one that uplifted many other species to create a diverse and tolerant galaxy.

Not so. Javik was there, and he explains that the Protheans were "might makes right" imperialists who ruled over many subject races. This insight transformed Liara's understanding of the Protheran Empire, and Javik has other secrets to share, too.

9 Kasumi: Cool DLC Mission

kasumi vault door mass effect

Most squadmates in Mass Effect 2 have a recruitment mission and/or loyalty mission to their name, and Kasumi Goto's loyalty mission is one of the best of all. Picture a classic "party infiltration" scenario but in the Mass Effect universe.

Kasumi needs to steal a high-tech graybox back from the crime overlord Donovan Hock, and Commander Shepard has all kinds of fun disabling the security around Mr. Hock's vault to break in... and then fight to escape.

8 Javik: Cool Design

Even the appearance of the Protheans was once unknown until Javik came along. He is a model Prothean, looking like a combination of Batarians, Turians, and Asari, but his armor is also unique.

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Protheans were once primitive predators, and they have four eyes. Javik's armor, meanwhile, is based on real-life samurai armor (for an archaic but stylish look) and the curvy, shiny carapace of a beetle. No other armor in Mass Effect is quite like this.

7 Kasumi: She's Fun

The squadmates in Shepard's crew vary from tough soldiers like Zaeed and Wrex to moody types like Thane to wise and serene figures like Samara. Then there's Kasumi, who always has something nice to say.

She's hardly a joker, but her upbeat personality and sense of humor really brighten the Normandy while she's on board. She loves beautiful things, nice people, and her deceased boyfriend, Keiji. And she's a good friend to just about anyone.

6 Javik: Unique Abilities

Javik can do some things that no one else alive in the galaxy is capable of. In terms of gameplay, he can use Slam, but he can also wield the unique power called Dark Channel, which is useful against most enemies.

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Meanwhile, he can also absorb information just by touching other people, from their genes to their memories and personality. Javik says that living things leave "markers" that Protheans can sense, and he's used to doing it to gain an edge on his enemies. He even found traces of Grunt in the Normandy's lower holds, and correctly realized that a tank-bred Krogan once lived there. Remarkable.

5 Kasumi: Infiltration Skills

Now for Kasumi's skills and capabilities. She is renowned for being the best thief and burglar in the business, but she's not in it for the fame. In fact, having a lower profile is better; she doesn't need that kind of attention.

No matter how tight a building's or vault's security is, Kasumi can break-in, and any bank vault, museum, or military base is a breeze for her to slip into (and back out of). She would make a good spy or saboteur, too, if she weren't already committed to her current lifestyle.

4 Javik: Stoic

Commander Shepard is charismatic and influential, and he or she can make friends with many diverse people and convince them to open up. Some squadmates are more stoic and firm, though, and they look cool in the process.

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Javik is positively unshakable, since he saw the full horrors of the Reapers' capabilities of the previous cycle, and he is getting used to being the last living Prothean. By now, nothing can scare him or upset him. He's a rock, and that's just what Commander Shepard needs.

3 Kasumi: Shadow Strike

Kasumi has a unique power too, and it is based on her stealth skills. She is not a full-time assassin like Thane is, but then again, she won't back down from a fight, and she makes for a great partner during the battle for Keiji's graybox.

Her ability is Shadow Strike, which allows her to become invisible, approach an enemy, and strike them down with a melee attack. That won't work against every enemy, but most ordinary soldiers will succumb before they even realize what's happening.

2 Javik: Vengeance Theme

Javik explains that during the time of the Protheans, each aspect of war and civilization would be represented by an avatar figure. How those avatars were chosen is unknown, but Javik was certainly one. He stood for vengeance.

He explains all this in a poetic manner, and now, he stands for the ghosts of trillions of Protheans who want Reaper blood spilled (that's paraphrasing his own words). Javik couldn't have asked for a better time for revenge, and once Earth is taken back, he gets it fully.

1 Kasumi: Acrobatics

kasumi goto mass effect

During a cutscene during her loyalty mission, Kasumi demonstrates some truly incredible acrobatic feats. Donovan Hock is in a gunship, and its energy shields are a serious problem during the final battle. So Kasumi goes on the offensive.

She leaps from surface to surface and clings to Donovan's gunship, then disables its shields and safely leaps away. She lands with ease, and now, the battle is about to be much easier, thanks to her incredible moves. No one else on Shepard's squad could have done that.

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