Lady Sif

The Warriors Three have had their time in the limelight, but the most popular of Thor's supporting cast is probably Lady Sif: a serious badass that's been on both the big screen and the telly.

Name: Sif
Race: Asgardian
Experience: 60 (Heroic)
Power Level: Four Color with Super Karma (55 PP)
Agility d10; Smarts d8; Spirit d6; Strength d12+5; Vigor d10
Pace 6; Parry 10 (2); Charisma 0; Toughness 19 (6)
Hindrances: Loyal, Obligation (M—Odin), Overconfident, Vengeful (m)
Edges: Arcane Background (Super Powers), Brave, First Strike, Counterattack, Frenzy, Combat Sense, Quick Draw, Combat Reflexes, Dodge, Level Headed
Skills: Climbing d4, Fighting d12, Notice d8, Persuasion d4, Riding d6, Stealth d4, Streetwise d6, Throwing d6
Inventory: Asgardian Armor (Armor +6, –4 ballistic AP)
Powers:

• Attack, Melee (4): Damage Str+d6, Multiple Attacks.
• Double Sword (7): Damage Str+d10, AP 4, Lethal, Multiple Attacks. Device (–2, swords).
• Deflection (1): –2 to hit, Protector. Device (–2, asgardian shield).
• Leaping (3): Level 2. Leaps 4" vertically and 8" horizontally. Death From Above.
• Parry +2 (1): Protector. Device (–2, asgardian shield).
• Regeneration (3): Level 3, rolls to heal every 10 minutes. Limitation (–1, Level 1 against Frost Giant decay).
• Speak Language (1): Written Word. Limitation (–1, only works on sentient species from the Nine Realms). (All-tongue.)
• Speed (2): Pace 12.
• Super Attribute (22): Agility +1, Strength +8, Vigor +2. 
• Toughness +6 (9): Hardy.

One of Asgard's most talented warriors, Lady Sif is a skilled combatant, wielding a double-bladed sword and a powerful asgardian shield. Thor, however, befriended her, granting her the recognition she deserved and elevating her to a position of power. Lady Sif was also once involved with a warrior named Haldor, but he was killed in the events surrounding the enchantress, Lorelei.

Lady Sif often joined Thor and his Warriors Three on their adventures, including following Thor to the surface of Jotunheim. After Thor's banishment, though, Sif's foolhardiness, along with the rest of the Warriors, followed Thor to earth to try and find him, as well as uncovering the lies Loki spun against his brother. Soon after, however, they were followed through the Bifrost by the Destroyer, Sif assisted with evacuating civilians, long enough for Thor to do what he needed to eliminate the threat and return to fight Loki himself.

After the destruction of the Bifrost, the Nine Realms were thrust into chaos, and Sif joined the asgardian forces to try and restore order across the kingdoms. After the invasion of Asgard by the Dark Elves, Sif helped Thor escape with Loki, and was assigned with Volstagg to deliver the Aether to the Collector.

Shortly afterwards, Sif was tasked with retrieving Lorelei, who had escaped when Asgard was invaded. Arriving at earth, Sif was assisted by Agent Phil Coulson and his team in capturing the sorceress, but not before she wreaked a decent amount of havoc among the humans.

Soon afterwards, Sif was sent to intercept a Kree warrior that arrived on earth, but had her memory wiped by his weapon. She was picked up by S.H.I.E.L.D., who helped her track down the Kree, but after it was revealed that he was trying to hunt down young Inhumans, Sif turned against S.H.I.E.L.D. to try and attack Skye. Shortly afterwards, though, she was convinced that Skye was not a threat and escorted the Kree back home.

As far as we know, Sif is still in Asgard, doing whatever is happening for Ragnarok.
—DoctorBoson