Well, after that rant about how I have no time to read/write anymore, it seemed stupid to me that I didn't. So I made some.
On the story. First off, is it chapter one or two? If it's two, why did you never post chapter one? (Prologues don't count as chapters... heck, they often don't even count as page numbers.) The use of present tense is very strange, and I only found one part where you slipped up and did past. However, the use of an "abnormal" form like that usually shouldn't be attempted without a specific reason or purpose in mind. I confess I've yet to see one here, but that could be revealed later.
I note you have an excellant grasp of diction, keeping the words both varied and appropriate... mostly. There were a couple points where I think you fell out of step and kludged together a sentence or two. But those occasional quagmires aside, the prose flowed rather well. I think that dialogue is, as you noted, one of the weak points. I notice two things that are likely the source of this. First off, the character you've chosen for erik (the viking?) doesn't seem to be worked out well. Now, I could be wrong, but you don't seem to sure of who he is and how he should act/talk. As such, you have him asking rather intelligent things one moment, and then really stupidly phrased things the next. So one moment Tam is having to answer a valid question, and the next he seems nearly patronizing. The general IQ of the conversation is all over the place and that makes the whole conversation rather jerky. The other thing that's hurting the dialogue is that you've got too much of it. You started a conversation, and tried to make it realistic, and explain everything via dialogue. Problem is, this doesn't work so well in books. If you have a principal you're trying to get across (like the idea that roleplaying a "character" is something done in normal life as well) you need to show it, and not just directly explain it. It's the classic example of the stupid character in a movie, who's only job is to ask stupid questions as an excuse to explain everything to the audiance. Yeah, it works for hollywood, but I would hope someone who aspires to writing would have higher standards than hollywood. :-)
Overall, not too bad. It's a bit shaky there at the start, and I worry you might be making Erik too flat/cliche of a character (total slob and video game addict) but the descriptions are good, and the flow works, and the premise shows potential. BTW, have you ever read "American Gods" by Neil Gaiman?
Thank you for commenting after the comment about not commenting Xeph. That made me smile quite a bit.

Lets start the answers with a bit of an explanation, I suppose. I've done a lot of my writing, recently, online. I do a lot of roleplay that way, you see. So, the present tense, despite how unusual it is in a novellisation, is something that I am quite used to, actually.
And I know that is
really strange. XP
I have to remember what I'm doing to write in the past tense again. And, it's gotten a little easier over the past few weeks, but several months of school with only a little bit of online time in your freetime, and no time to spend with books like you used to....eh....it's been a little while.
So, there's my wonderful not-so-excuse for the present tense. It's good to know I can pull it off, though.

The story itself was actually a thought of mine to do a comic. I have a 4-chapters finished story of another idea that I am working through, done in the same style, except it is visualized like an anime. To clarify, it is written as if you are watching a show. Not in script form, and not in past tense. It is written as if every second goes by in real time.
I guess I also took that particular 'fetish' of mine into this one, too. Apologies.
Chapter One is a short one shot, and is only a couple of paragraphs long. I decided to skip it and put chapter two in with the prologue because the prologue gave a little more of an idea for what was going on, and the 2nd chapter started with the real meat of the situation.
I have since decided to scrap the entire chapter and start over, actually. It has taken me this long to respond because I am trying to finish it, so I can show you what I am capable of writing when not using present tense or visual imagery - as I have done for some time now. I have not finished yet, but I thought that I'd waited a little
too long to respond to your very well-appreciated comments. It was, and is, about time to get back into the swing of things in the forum.
I agree with your assessment of Erik. He is not very well defined. Part of the problem is that Tam
is. I don't a lot of his backstory yet, but I know
of him, and he has become more of a person than a 'sketching' to me (more than a scattering of random thoughts pieced together in the semblance of a person).
Another part of the problem is that I am just not very comfortable with portraying college males, I guess. I am in college, and I
know guys who are, but....meh.
But, I am working on it, and hopefully when all is said and done, you will allow me to repost and let me show you some improvement.

That being said, I have never heard of Neil Gaiman. Most of my reading habits had been restricted to the fantasy section of the library (Weiss/Hickman, Eddings, Brooks, McCaffrey, Lackey, Williams, etc.) because I found them to be more enjoyable and understandable than science fiction (a lot of the terms they use were confusing to me in high school. I haven't tested myself on them in a while - that might not be true anymore), and because I found other works of fiction to be 'boring'. Which is, I guess, another way to say that I had certain expectations of what should go into a book, and if the book didn't have it (have a certain degree of 'magic' or 'fantasy') then I wasn't interested.
Things may be different now, though. Got any good suggestions?
