There are plenty of easier ways for him to do it, no one knows where he is most of the time, he could just sneak up on Harry under a veil, kill him and say he was out Gatekeeping if anyone asked.

OK OK.  I will sleep on it and think more about it tomorrow.

Just like you need a conscious mind to use hellfire/soulfire? or different?

1 ) Harry usually has a few supporting characters in each book.  Who do you think will be the main sidekick in Cold Days and in what way will they help?  Who else will have a significant contribution to the plot?

Elaine-While stuck in winter, he will be using Elaine to get info from the outside.  This will be accomplished with a Lash-boosted mind-link spell, and go on behind Mab’s back.

2 ) At the end of Ghost Story, Harry has said goodbye to all his friends in Chicago. 
a. Who will be the first friend to find out Harry isn't dead? 

Ivy – While Harry is stuck in Winter, he will send a message to Ivy indicating his state of non-death.  If it is just the friends from Changes, Thomas, when he comes to get help from someone he can trust, and is least likely to beat him up too much.

b. What shenanigans/snark will Harry use when he "re-appears"? 

Harry, Dressed in Winter White, will say while talking with Sanya “See I told you I was Gandalf”

c. Who will have the coolest reaction?

Thomas – A conversation about how the CPD still has his boat as evidence and how Harry will be paying for fixing the hole and a new paint job.

d. Who will have the most touching reaction? 

Maggie – Harry will change his mind about wanting to be out of touch with Maggie.  He will let her know that once he has a place, she will be welcome to stay with him.  Much outpouring of emotion from Harry, much confusion and reluctance from Maggie.

3 ) In nearly every book, Harry usually comes up with a new powerup/tool/way of making things go boom.  Given that he just became the new WK, what new abilities will he rely on and which new ability will be the most useful to him during the story (and how)? 

Opposition magic will be his new goto ability.  Fire and Ice, Air and Earth will each be combined in spells to produce exciting and disastrous results.  Darkness will be his power-up.  I am not exactly sure how this will manifest, but the coolest thing I think will be transitioning through darkness (shadows, lakes, etc) both to and from the NN.

4 ) Harry generally has a "Big Bad" to worry about.  In fact, according to the blurb, Harry is going after someone very specific.  Who will that enemy be, and how will Harry take him/her/it down?

Lash/Lasciel.  Mab does not want someone mucking about Harry’s head (except Mab).  Harry will be tasked with defeating Lasciel.  To do this, Harry will have to take up the coin and engage in direct confrontation with Lasciel to finally free him from all links to Lasciel.  Harry will keep Lash around just to tick Mab off.
Additionally, the Fomor will be setup as a Big bad to deal with, but only so far as a particularly big brute, not a higher up.  Higher up Fomor will be dealt with later.

5 ) Harry usually faces some sort of "Choice" in every book.  A point where the easy way out will cost his soul/humanity in some way. According to the blurb, this book will be no different.  What will be the most crucial "choice" Harry makes?

Harry will have to Choose between Lasciel and Mab.  Lasciel will reveal some motivations separate from Nic’s motivations.  It will involve offers for Harry tapping into the energy released from Chichen itza, the Dark Hallow, or (most likely) Demonreach.  Time travel will be floated around as well to taunt harry into accepting.  This offer will include fixing Molly and Murphy because Harry will have never left.

6 ) As the new Winter Knight, Harry is pretty much garunteed to encounter his Summer counterpart -- Fix.  What will their interactions be?  Will Fix survive?

Fix will be working with Harry to stave off the Fomor threat.  These battles will take place largely in the NN, but will involve denying real world gains by the Fomor.  Fix will treat Harry like a trusted enemy, while Harry will constantly be asking fix to loosen up.  Harry will say he killing Fix would not be a mission Harry would accept, while Fix will continue to believe that Harry will not have the option to decline.

7 ) Jim has mentioned that it's about time now to start revealing some of the motivations/dealings of the shadowy figures working behind the scenes (i.e. what Harry calls the "Black Council").  What Black Council secrets/actions will be revealed in this book?

Mordite trafficking will be a subplot for Harry to follow-up on.  Tracking the Mordite will supposedly lead to black council wizards, but will actually lead Harry to Senior Council Wizards namely, the Merlin, McCoy, Listens to Wind, and Liberty.

8 ) There are many WAG theories on the boards.  Write up to three WAG theories you believe are correct that will be confirmed (or at least have evidence in favor of) in Cold Days.

A) Harry’s Title of ‘Za Lord is more than just idle talk.  Mab will confront him on challenging her authority by gathering his own private army and appointing himself lord.  A lesson in Names having power will be provided by Mab.  This will be setup for the creation of a post of Winter King or Autumn/Spring King-One for the Harvest, and One for the Hunt.

B) Mrs. Mouse/Mouse’s Twin will be conceptually but not physically introduced.  The Idea of Foo Dog Pairing will be brought up by Mai, and the strangeness of his loneness will be highlighted.

C) Mab (or her proxy) fixed little Chicago.  She did not want to lose her prize or fulfillment of the bargains, so she fixed it.  As Leah was tasked with looking after Harry, Mab viewed it as her responsibility to prevent Harry’s Head from disintegrating.

9 ) Extra credit:  Write down any prediction about that you think might improve your final score.  Only issues aluded to within Cold Days will be counted. 
The Rifle will be a gift from Kincaid.  It will have bullets that are particularly effective against Fae, and more effective on the more powerful Fae.  It will be a sorry I didn’t kill you gift.