Your Favorite Sidekick

From Luigi to Tails to Navi, video game Herod and heroines usually have a companion that they're closest to; who they trust to valiantly travel and save the world with; someone who always has their back. Sometimes, like in Navi's case, it's not the most regular way of helping link, but she's still an asset to Link's team. My question is, which sidekick character is your favorite and why? Who's your least favorite and why? What do you think the importance of sidekicks are in video games?

Discuss here!

Sparx the dragonfly is my favorite sidekick. I love the Spyro games and Sparx is a big asset. I'm glad they gave him a few levels of his own in Year of the Dragon and subsequent games. I'm not sure who my least favorite would be... Sidekicks offer more gameplay value and add to the story. They can also add humor to a game because they don't have to take their role as seriously as the main character.

Knuckles from Sonic the Hedgehog series is one of my favorites. He's able to break giant boulders with his fists, could climb mountains and dig through the ground easily, and he's the guardian of the master emerald. Oh, and he could glide, too! That's pretty cool. Epona from the Legend of Zelda series is my also favorite. She helps you out a lot during your exploration throughout the Hyrule kingdom, and regardless of where you are, she will always come running to you as soon as you play her song. She's the greatest horse a guy could ever have.

definitely elena from the uncharted series. i love how in the first one she is just witty and makes smart comments to nate. she actual helps in the game by getting down ladders and shooting against the enemies. she's great!

I don't know why, I have always loved Vivian from Paper Mario (I had to add Bow and Baby Yoshi). In general, all of the partners from Mario RPG, Paper Mario 64, and Paper Mario Thousand Year Door (THE BEST ONE), and Not the "partners", or I would say, "scribbles", from whatever the Wii Version.
I miss the Paper Mario Series, in my opinion the sidekicks MADE the game!!!
Since Super Paper Mario, the series has been six feet under without a sewer pipe in sight.

Mine is also from the Sonic the Hedgehog series, but I always liked Tails over Knuckles. His shy personality but desire to be as helpful as possible to his friends reminds me of myself, which makes me sympathize with him when Sonic does things horribly wrong, haha. Other than that, he's amazing with technology and his propelling tail probably got him interested in being a pilot, which he is in the games. His humble attitude is warmly welcomed in every Sonic game and his presence improves a scene or level tenfold. Although the Sonic series wouldn't be the same without the brave blue main character and the overly confident Knuckles, Tails brings an element to the games that exponentially improves them.

Fi from LoZ Skyward Sword. She can be annoying but she does help a lot, even more so than Navi from Ocarina of Time. Plus she is the living embodiment of the Goddess/Master Sword, that's kinda cool.

I didn't even have to read past the title to know that my answer would be Tails. In fact, I'd go as far as saying I like him more than Sonic himself. And I'd have to echo a lot of what Apple Juice said, in that Tails has a very interesting character and personality, and is always a great addition to those around him. Oh, and it's hard to beat a name like Miles Prower.

Simon "Ghost" Riley (MW2)
Yuri (MW3)

Frank Woods (BO)
Mike Harper (BO2)

Thel 'Vadam "The Arbiter" (Halo 2 - 3)
Emile (Halo: Reach)

Those are the ones that come to mind.