Jacks rule so they go first.
Deathjack: An amazing brute with a deep grid, terrific stats and a plethora of unique abilities which make this jack the finest in all the IK. With two P+S 18 attacks, arm 19, two free focus every turn and the ability to cast spells and consume. souls the DJ has no equal on the battle field
The DJ suffered a few substantial nerfs in MKII but none are overly worrisome. Firstly the DJ can no longer necrovent but as a trade you no longer have to feed it a FOC to keep it from going crazy. True that loss of fluff tames the dj down a bit but ultimately it's for the greater good, er, bad.
The Nightmare is my favorite jack in the game. This speedy son of a bitch has earned more kills than I care to count. As far as I can tell the Nightmare is essential in almost every cryx list and especially with Mortenebra.
While spd 6 is great for a jack, with Morty the nightmare can potentially move 23" in a single turn. With 2". Reach the nightmare has an effective threat range of 25". Game Over.
The nightmare kept its bond with Deneghra so that while in her battle group it gains stealth. The imprint "ghostly" is fantastic in that it let's you ignore free strikes and terrain. If only it ignored intervening models.
On the down side the nightmare's grid is shallow for a heavy requiring you to play with a tad more finesse than with other heavies. All in all the nightmare is A+
The Seether: was pretty cool in MKI but was rife with issues, namely I played infantry machine and never ran much more than a few nodes and the Cankerworm. That being said, MKII has provided some serious incentive to fielding jacks so now the seether shall see the light of day.
With MAT 8 and one free FOC per turn the seether is nigh but guaranteed to box whatever it charges. MKII granted the seether a chain attack which allows it to make a power attack for free. (With some exceptions). Frankly this jack, while more expensive, has taken the Cankerworm's place on all my lists. So again, great MAT, better DEF than most heavies (irc), decent pow+str, two open fists, a deep grid and decent movement makes the Seether another A+ jack.
The Slayer is still the red-headed stepchild of all Cryx players. Its utility was increased in that it is now cheap as dirt for a heavy and boasts a killer pow 22 combo strike. This little guy on a charge is going to cause some serious grief. Lamentably with low armor and a shallow grid the Slayer isn't going to last long after its initial assault so pick your targets well. Overall rating is a solid "B-"
The Leviathan is a confusing jack. I don't own one, and with its current stats I'm pretty sure that will go on unchanged. There is really nothing special about this maritime heavy. It looks cool. Has a ranged attack with ROF 3 and a cool looking claw. But, well, that's really it; and it's as expensive as the nightmare or seether, both of which I'd take over the levi' any day. Overall grade "D+."
The Harrower is still cool. Pricey and "OK." As of yet I don't know why I'd take it over the nightmare.
The Stalker is perhaps the one jack which benefited from MKII more so than any other jack in the faction. Let's be honest now, the stalker was a sissy, waste of time, no good wreck marker waiting to happen. Now, while still a wreck marker waiting to happen, the stalker comes with a few added tryx and the potential to be an assassin. Honestly though the damage grid on this glorified bone jack is so pathetic that even taking into consideration its high def and cool abilities the jack is still scrap. "C"
The Cankerworm is no more. I'd prefer to not talk about it. You bastards! You know who you are! "F"
Nodes: single in purpose and mind though different in cost. Much energy was spent on an in faction argument concerning the nodes and their steep point cost. Mostly it was one dink saying "they are fine" vs the Cryx community. Ultimately the community prevailed as PP recently updated the stats for the nightwretch and defailer. Same points as before but the defiler finally has the spray attack it should have always had and the wretch has "powerful shot." Awesome. For still being too expensive and because I say so, the nodes get a "B."
To Be Continued...