Winter Knight's Mantle

The Winter Knight's Mantle is the power, or Mantle, bestowed upon the Winter Knight by the Winter Queen. It is first mentioned in Summer Knight.

Description
Winter Knight's Mantle is the power conferred by the Winter Queen to a mortal chosen to be her Winter Knight.

In Cold Days, Harry Dresden refers to five prior holders of the Mantle, his predecessor Lloyd Slate, Gilles de Rais, Friedrich Haarmann, John Haigh, Andrei Chikatilo - four of which were serial killers who preyed primarily on children.

Dresden describes it as a "cold, clear power". The Winter Knight is a very powerful weapon to the Winter Queen but it is double-edged. The Winter in the Knight comes from the Queen but she is just as vulnerable to the Knight as any other Sidhe. The changes to the bearer start with strong impulses and intense emotions and then build exponentially.

Any iron alloy that gets into the knight's skin disrupts the Mantle's power. Also, Butters posits that Mab fiddled with the pain threshold so that her knight can plow through her enemies without stopping even for knife wounds.

New abilites

 * Ice Enhanced Spells: Winter Court power in his spells using ice in various manifestations.
 * Strength and speed: Harry Dresden runs faster, without getting tired, in the FBI headquarter, even faster than Susan Rodriguez. Dresden cracks the sternum of a half-vampire with a kick.
 * Heightened vision.
 * Mab's Voice: gives Dresden a protection of frost as he starts to weary and slow down on the stairs of the Temple of Kukulkan, reviving him with renewed energy and strength.

Summer Knight
In Summer Knight, after capturing the traitor Lloyd Slate, the current Winter Knight, Mab asks Harry Dresden to take up the Winter Knight's Mantle and all of his debts to her would be cancelled. He refuses.

Dead Beat
In Dead Beat, Mab stops answering his questions about Die Lied der Erlking and the Heirs of Kemmler because she will not give information for free. For the second time, Mab asks Harry Dresden to take up the Mantle—she will cancel his debts and answer all of his questions freely. Once again, Dresden refuses.

Small Favor
In Small Favor, Mab charges Harry Dresden with his second task for her, to find Marcone who had been abducted. And for the third time she asks him to take up the Winter Knight's Mantle, and again Dresden refuses.

Changes
In Changes, desperate, having just broken his back and unable to save his daughter from the Red Court vampires who abducted Maggie for a ritual Bloodline curse sacrifice in Chichén Itzá, Harry Dresden summons Mab and bargains to take the Winter Knight's Mantle for the power and strength and restored health of his body and the time to save Maggie. They make a deal and to seal it, Dresden had to sacrifice Lloyd Slate on the Stone Table with Medea's bodkin.

Cold Days
In Cold Days, Bob explains to Harry Dresden that it doesn't makes sense that Mab would want Maeve killed since the Mantle would simply pass on to another who would become another "Maeve" since the Mantle changes that person who wears it. Thomas Raith advises Dresden not to ignore the predatory impulses of the Mantle, so to be in control of them.

The instant that Dresden utters: "So, screw Winter Law—", the Mantle disappears. Dresden is filled with intense pain and fatigue and his body goes completely numb from the waist down. He can no longer hold himself up or control the functions of his lower body. Not only is the Winter Knight's power taken away, but his body is returned to the state it was in prior to taking on the Mantle. All this comes back a moment later.

The power of the Winter Knight's Mantle restores Harry Dresden's shattered body, and gives him strength, speed, endurance to the limits of human ability, and possibly more, so long as Dresden obeys Winter Law.

Skin Game
In Skin Game, Harry Dresden put on thorn manacles before the heist began, and this prevented not only his magic, but also the Mantle's. Immediately after this occurred, every injury came back to him.

The power of the Winter Knight's Mantle was able to prevent Dresden from freezing and also from slipping on the completely smooth ice ground when he faced the Gate of Ice.