Prologue: Location: Hyperion V, 18 months before the advent of the Badab War.
Traecar, librarian of the Mantis Warriors and tech marine Reporis stood on top of a long, wind-swept ridge 3 klicks
SW of an abandoned ork Mek Works. Yesterday's "action" against the Doom Eagles was on both of their minds as they stood silently, surveying the desolate scene below. What would bring the Doom Eagles to this site at this time... just when a mission of such importance was necessitated in the compound below?
"What are the odds...?" asked Treacar, more to himself then his engineer.
"Immaterial." answered Reporis.
"I wonder what has brought the Doom Eagles here at this time, odd coincidence... don't you think?" asked Trecar.
"Also immaterial."
Traecar gritted his teeth... sometimes the innate analytic nature of the technical specialists was, well...
"My dear Reporis, in your technical training regime... was there a class on being irritating, or do you come by your talents naturally?"
"Immaterial." replied Reporis... but Traecar could "hear" the smile creeping across the engineer's lips.
"Bloody tech" Traecar thought... but he couldn't help smiling himself. Such were the extent of the jokes in the chapter these days... with talk of resistance against the bureaucrats of Terra who had so shamefully treated the chapters that guarded the Imperium from the Maelstrom, belly laughs were had to come by.
Traecar paused to let the moment pass before getting back to business. "None-the-less our attempt at dissuading our brother Astartes from entering the compound yesterday have clearly failed. We just have to hope they're as isolated and without access to reserves as we are."
"Yes sir" replied Reporis, "other than fuel and a little paint... neither side sustained any loss of man or materiel, so we can expect to meet the same level of resistance today. I take it diplomacy has failed?"
"Diplomacy..." (Traecar shook his head) "with talk of rebellion in the air, there is little diplomacy to be had. No brother, I'm afraid we're going to have to do this the old fashioned way."
Reporis spoke. "I suggest we roll in quickly with the Razorbacks to secure the wounded Mentor and the traitor. A quick smash and grab operation should get us out with minimal casualties."
"Agreed Reporis, but... you're holding something back... you may speak freely."
"Sir, our scanners indicate a hidden cache of jet bike parts on the premises. You know that we are one of the only chapters to still maintain operating jet bikes and no forge world had made replacement parts for centuries. The opportunity to get these vital parts is unique. I believe this is why the Mentors were here in the first place."
"Hmmm... perhaps the arrival of the renegades was fortuitous after all. Preventing the Mentors from claiming the prize they sought... such a thing would have great value to them." mused Traecar. "Very well, we'll add it to the list. Get the men ready to move, it's time to claim what is ours."
You may read about the first battle
here.
The Armies: Mantis Warriors: HQ: Libby (stock) - avenger, VoD
Elite: Tech Marine (stock)
Troop: 5-man
tac squad in las/
plas razorback, srg w/
PS Troop: 5-man
tac squad in las/
plas razorback, srg w/
PS 
I have for some time, been looking for a decent 500 point build for marines. This is the first one that I've actually liked. It's mobile with some heavy fire power in the razorbacks. The libby gives it some punch and the tech marine gives me a
de-facto power fist as well as helping to keep the razorbacks in good repair. I didn't realize how completely useless a 12" range "heavy" VoD would be... don't think I'm likely to take that again. Gate would probably be better to move the libby and squad around quickly should their ride get toasted. This seems to be a good expeditionary force. No scouts, but entirely mobile and self-sustaining.
Doom Eagles: HQ: Libby w/ jump pack - force dome, machine curse
Troop: 5-man
tac squad, srg w/
PF in rhino w/
HK missile & dozer blade
Troop: 5-man
tac squad
Hvy: Predator w/ autocannon & 2
LC 
I did show him my list before he picked his own. He wanted to make sure he had enough anti-vehicle armament, thus the predator,
HK on the rhino and
PF in the squad, not to mention the machine curse of the libby.
We rolled for the mission and got "Take and Hold" with "Dawn of War" deployment. We rolled & got 4 objectives... here's how they were placed.
Objectives: 
My two objectives (traitor
MW & wounded Mentor) are on the left of center, his two are on the right
I won the roll off and chose to go first.
Deployment / Turn 1 
We both decide to roll on in turn one to avoid the whole shenanigans of
DOW deployment. This is also why the turn text on the rest of the photos is wrong... this isn't really "deployment", it's turn #1. I roll on behind cover and in easy position to reach both of my objectives. Once again I keep my two razorbacks close to one another for mutual support. During his half of the turn, my son comes on a bit more spread out but as I did, covering his two objectives. He uses the exposed unit to cover the rear objective which I am unlikely to challenge (smart).
Turn 2 
In my half of turn 2, I quickly move both of my razorbacks into position near my two objectives, securing both the wounded Mentor and the traitor Mantis Warrior. My son remains cautious and only moves his troops in to immediate contact with his rearward objective.
Turn 3 
If I'm going to have any chance of a win, I've got to drive him off of one of his objectives, even if I can't claim it myself. My two squads disembark and move to hold my two objectives while the razorbacks with libby and tech in tow go-a-hunting the rhino. My son wisely abandons his forward position, but for some reason is still unsure what to do with his predator to support his forward troops.
Turn 4: Mantis Warriors 
At this point I see that my troops have become vulnerable to the crew in the rhino, so I move one Razorback to discourage his claiming the secret cache while moving the other to support my troops holding the traitor Mantis Warror (nasty bugger!).
Turn 4: Doom Eagles 
I forgot to take a pic of this phase, so I had to cut-and-paste from the next turn's pic... sorry. Seeing his opportunity, my son moves in for the kill and guns down two of my marines with bolter fire (two wounds, I failed both saves) and my marines fail their leadership and fall back the maximum (12"), so now I've been driven off MY objective and he's in position to claim it! The little rat!! No respect for the elderly!
Turn 5: Mantis Warriors 
This situation may not stand! So my two characters pile out of the razorbacks and an appreciative amount of AP3 or better fire power unloads on the poor Doom Eagle tacticals... killing them (just barely) to the man.
Turn 5: Doom Eagles 
My son finally moves his predator into position to command the center of the buildings (honestly in all the excitement over what was happening around the rhino I think he just forgot about it). The rhino tanks shocks my squad in the hopes of keeping it moving off the board, but the Mantis Warriors simply step aside. The rhino almost got stuck on the rubble pile, but was able to bulldoze it's way out again. The predator however managed to take out a marine with it's autocannon. This time however, they pass their morale test.
-- We roll, and the game continues. --
Turn 6: Mantis Warriors 
I move my infantry and both
ICs to claim the objective, making sure to put my Tech Marine in the front so that any tank shock would (hopefully) have to go through him and his servo arm. I pepper the rhino's hull with las cannon and plasma fire... but little did I know that the rhino had been up-armored with some fragments from a Warhound's carapace found on an ancient battlefield a week prior... so my shooting had no effect.
Turn 6: Doom Eagles 
Now at this point... I had assumed that he would tank shock my troops on the objective and go for the tie... but instead the little rat decided that mayhem was more interesting than a "dull" tie & he rammed my Razorback, Immobilizing it!! The predator tried to shoot my marines off the objective but armor and cover held true... the traitor remaining in Mantis Warrior custody.
-- we roll, game ends! --
Final tally: Doom Eagles: 1 objective
Mantis Warriors: 2 objectives
Mantis Warriors win!
Another really fun game and he did some great stuff with that Rhino and short
tac squad. Honestly I think if he got a little more gutsy with this Predator and Librarian (or even remembered them) I'd have been in real trouble.
Epilogue: (Reporis, muffled, from the back of the damaged Razorback) "O.K., try it now!"
(Treacar turns key and stomps on the gas.) *Kranketa-kranketa-kranketa-kranketa - whirrrrrrrr..... cough, gasp, klunk*
Reporis: "Dont step on the gas, you're flooding it!" (mumbles) "Dang egg-heads."
Trecar: "What??!"
Reporis: "Nothing Sir, give me a moment!"
...and so it goes...
- finis -