In looking at my armies, it looked like the only one I was able to field at 75 points on short notice was Cryx, so after tinkering with a few things, I settled on Black Industries under Goreshade, ending with this:
Cryx Army - 75 / 75 points
[Theme] Black Industries
(Goreshade 1) Goreshade the Bastard [+27]
- Deathjack 
- Deathripper [0(6)]
- Deathripper [0(6)]
- Leviathan 
- Reaper 
- Seether 
- Slayer 
- Stalker 
- The Withershadow Combine 
Machine Wraith 
Warwitch Siren 
Warwitch Siren 
I figured Rob was likely to drop either Karchev, Harkevich, or Butcher3, and I thought I had a decent change in any of those matchups.
Rob showed up, and we rolled for scenario, getting Standoff, with circular zones to our left and right, and rectangular zones near each of us, with an objective in each zone.
Turns out Rob did bring Karchev, and brought the following:
Khador Army - 73 / 75 points
[Theme] Jaws of the Wolf
(Karchev 1) Karchev the Terrible [+30]
- Behemoth 
- Decimator 
- Grolar 
- Juggernaut 
Kell Bailoch 
Widowmaker Marksman [0(4)]
Yuri the Axe [0(6)]
Battle Mechaniks (min) 
- Battle Mechanik Officer 
Kayazy Assassins (min) 
- Kayazy Assassin Underboss 
Widowmaker Scouts 
Rob won the roll to go first, chose to do so, and deployed.
Rob runs everything forward, except for Karchev, who casts Countercharge, and advances forward. His goal was to put pressure on the zones as much as possible, forcing me to engage.
I respond by basically doing the same- I run and advance everything forward, matching the Deathjack, Leviathan, a Warwitch and Deathripper against his Kayazy and Behemoth in the circular zone to the left, the Seether, Machine Wraith as my primary threat on my right, and the jacks mostly moving towards the middle.
Goreshade advanced and cast Lamentation and Shadowmancer. I realized at this point that Shadowmancer was CMD range only, meaning I had quite a few things out of position and without Stealth, but nothing I could do about that now!
|End Turn 1|
He starts his turn by firing the Behemoth at the Leviathan, who is not Stealthed due to being outside of Shadowmancer range. With Carapace, however, he only manages one damage on the jack. He runs the Kayazy into my left circular zone, and into combat with some of my jacks, to try to stop them from having easy movement lanes.
I actually thought he might try something different here, running the Kayazy, and using them to screen the Behemoth (as I can only kill so many with the forces on that side). Maybe he felt he didn't have enough bodies to do that.
Anyway, the Widowmaker unit on my right basically does the same thing, running to engage my jacks after figuring they probably wouldn't be great against all the Stealth he was facing. Primarily, he was hoping to block off my Reaper, which I was planning to get into a position to drag one of his heavies out out of position with, to allow a Slayer or Seether to kill. The Widowmakers don't have a free strike to fear, but they did block up some table space that I wanted to use. To further prevent my plan, he ran some Mechaniks in front of his jacks, to prevent any pulls I would attempt.
|Mid Turn 2|
Goreshade upkeeps Lamentation (with the Withershadow Combine), moves up a little, and casts Shadowmancer again.
On my left, I get to work killing Kayazy, as the Behemoth isn't in the zone, and I figure I'd play for scenario. I kill all but two Kayazy, but fortunately those two weren't in the zone, so don't stop me from scoring it. I end turn, and Rob scores one point to my two, giving me a net 1-0 lead.
|End Turn 2|
Rob continues to work to eat through my forces. On my right, his Widowmakers get within five inches of my Warwitch Siren, and shoot her off the board. The Grolar moves backwards and kills my Stalker, freeing infantry and Yuri. His Decimator received Magic Weapon from the objective, moves into the forest, and kills my Machine Wraith, giving his significant advantage in that zone.
He shoots with to no real effect with the Behemoth, mills around a bit with Karchev and the Juggernaut, moves a Kayazy into the left zone to contest it, and ends the turn. He ends up scoring two points (one for his rectangular zone, and one for the circular zone on my right) to my one, tying us at 1-1.
I am in full scenario mode now, and decide to grab some points. On my left, I use the Deatjack to kill the lone contesting Kayazy, then use the Leviathan (which I've allocated an additional focus, and given it one from the Warwitch Siren) to move up and shoot the objective, destroying it (yay for generating three shots!). This gives me another scenario point, putting me at 2-1. On my right, I work to chew through the bodies that are there, but I'm wary of getting too much closer with Karchev and his jacks there. I kick the Reaper further to my right, and drag/kill the Mechanik UA. I'm pretty comfortable with how things stand, and pass my turn. I score two zones to his one now, a net plus one for me, and our score goes to 3-1.
|End Turn 3|
Karchev starts the turn allocating focus to the Juggernaut and Behemoth, then backs up to cast Road to War (in order to get out of Goreshade's Lamentation range), then pops his feat.
Kell decides to come out and play, and moves up. Before he can shoot, I decide to Countercharge with my Seether, killing him. The Widowmaker Marksman on my right moves around, and shoots and kills the Deathwalker, triggering Road to War on the Behemoth, who promptly charges and kills the Deathjack in two attacks (holy crap!). Fortunately for me, he's too far away to take out the Leviathan as well. Eesh.
The Grolar on my right charges my Seether, and disables on of its arms. The Juggernaut follows up, killing the Seether and the central Deathripper. I'm starting to lose the attrition game- Rob is up in my face now, but I'm doing great on scenario, as I score a point at the end of the turn (in my rectangular zone). Due to Rob's movement, he scores nothing, giving us a score of 4-1.
I start my turn needing to score two points to win, and I have two different paths to do it. I'll be able to score my rectangular zone so long as I don't move anything. On my left, the Behemoth is the only model contesting the circular zone, and if I kill it, I can score that zone. Alternatively, Rob's rectangular zone is sparse- just three Mechaniks defending it. If I can clear it, and get a jack there, that could be a point too.
I realize I have the tools to try for both alternatives, and can just hope ONE pays off. I start by running my remaining Deathripper into his rectangular zone, giving me an Arc Node, and a jack there. I have the Warwitch Siren give a focus to the Leviathan, who moves a bit, then takes a few shots at the Behemoth, doing about seven damage. I activate Goreshade, pop his feat (but didn't really bother setting up my Bane Warriors yet, they were going to be placed to go after the Behemoth), and arc Bleed through the Arc Node, needing fives to kill Mechaniks. I have three to kill, and manage to get the rolls I need, clear the zone, and win the game.
My first Mk3 win! I was definitely helped by the fact that I focused on winning by scenario instead of trying for a caster kill (end of Turn 3, I gave it some thought, but decided to stay the course). I was doubly helped by the fact I feel my army matched up well against his- his shooting was ineffective against my Stealth, and Carapace made the shots hitting my jacks a non-concern. I was also helped by the fact I had a longer threat range than Rob's army, unless he could trigger Road to War.
I struggled to find an opportunity to use my greater threat range, as Rob wisely jammed his infantry down my throat, but knowing it was there kept Rob from playing more aggressively, which helped.
I quite like how Cryx plays- it's similar enough to how it went in Mk2, but man, I have a lot of work to do to make these armies competitive. Thankfully, it seems like the interest for more games is there, so I'll have ample motivation to get to work!