I am curious about the scale and type of warzone others are using in their playtesting, so I thought I'd ask here. How many of you are using a single regiment front, vs. a large crusade force? Against what enemies? And with what sort of Regiment as the PC unit?

For my own stuff, we're playing the story of the 3rd Solan Airborne Regiment, a Fortress World Drop-Troop regiment specialized in fighting Eldar pirate raids, as they are sent as pathfinders for a large crusade force to punish a planetary government found to be in collusion with the xenos. Millions of Guardsmen are involved, landing to face off against both the governor's treasonous forces and the treacherous (yet oddly helpful to their human ally, which should make anyone who knows Eldar suspicious) xeno forces. Players' missions will mostly be behind-enemy-lines airdrops to eliminate AA or artillery, or otherwise hit high value targets to allow the main crusade force to sweep forward more easily.

I've run two one-shots so far, both set on a world of my own devising.

Avernus is a rich Hive World, the capitol of the system it's in. Massive salt flats separate the massive promethium refineries and various mining sites. The planetary governor, a Lord Severus Grave, declared independence from the Imperium of Man. A mercenary army, roughly 60% of the planet's local Guard regiment, 90% of the PDF, and the Black Hand warband of traitor astartes conquered the surface of the world, while a fleet of reavers funded by the planetary nobles kept a blockade in orbit. The loyalists eventually held only Hive Malbolge.

The Imperial Navy managed to crush the blockade, but orbital bombardment was deemed out of the question due to the very volatile and very valuable promethium. A force of Elysian Drop Troops and Cadian Shock Troops were dispatched to aid the few remaining Avernus "Avengers" Hunter-Killers. Operating out of Firebase Czernobog, the loyal forces have put up a good effort. Heavy air support from the Avernian 18th Fighter Wing has proved invaluable. The war has now been going on for around six months, and is considered to be going in favor of the loyalists, albeit slowly. Several traitor generals have been assassinated through joint ops with the Ordo Hereticus.

The populace at large seems disloyal to the secessionist, and the motivation behind his declaration are unknown. Many hope the end of the war is near, and that the planet can soon return to proper Imperial rule and profitable promethium exporting.

My group are currently defending a small starport on the Pleasure planet of Halvmork, I had already been running a Deathwatch game where the Astartes saved the remnants of two companies of Imperial Guard that were the honour guard for an Imperial Guard General who was on the pleasure planet having a meeting with Administratum members and Planetary Governors in an attempt to organise improved supply lines.

When we decided to test Only War I decided to interject it as part pf the campaign I was already running. It has caused a few minor issues due to the limitations that has imposed but for the most part it seems to work fine.

E

My group practically demanded I place them in the Jericho Reach in the Canis Salient. They're not fans of the Tau and well, it's their funeral.

"This is Testament of His Mercy, Imperial Grand Cruiser. We have mutinous crew on board. There was a forced real space reversion. By His light the ship survived intact but engines are offline. Sections of the hull are still burning. Unknown number of crew dead. This is a general distress beacon of Testament to His Mercy. We are in an unknown system. We are caught in the gravity well of a planet. Auspex scans going out with this message. May He watch over us. May His light light our…"

"Gentlemen this message was received 3 months ago. Astropaths have tracked it to this world. And a hellish one at that. Testament has gone down on the ice covered northern continent. Average day time temperature sits just above -30. It is a tundra out there. Survivors have clustered in the stern section of the cruiser with all the command and control systems. Unfortunately the rebels have taken up positions around the bow and out into the wilderness. They have set up long range artillery batteries, anti-air defenses and other weapons from the looted stores."

The general looked over his senior command staff "By we are the Death Heads. We will grind these traitors beneath our boot. Fleet has scanned the crash and the sites of the traitors. Planetary strikes will begin in the next hour. Once they cease the entire First Regiment deploys via drop pod to secure the wreck and to relieve those who remained loyal to His Throne. They may seem ragtag but true numbers are currently unknown to us. But we are the Imperial Guard. We will not fail!"

Hour later when the ice was broken and the pristine tundra was naught by ashes and dust the sky will filled with what seemed shooting stars. From hidden bunkers and remote sites the artillery of the traitors lit up the sky. Many of His warriors never made it to the ground, but their sacrifice ensured that others did.

4 weeks into the mission both sides have secured themselves further in their positions. Without clearing the enemy from their positions the heavy lifters and bulk repair vehicles of the Mechanicum will never be able to rip the Testament from her icy tomb. If that wasn't bad enough Astropaths said they are detecting another fleet approaching… it is the Lost and the Damned. They have come for a new ship bringing with them the vehicles of the Dark Mechanicum and other foul things.

Can the regiment hold its position until Imperial reinforcements arrive? Or will they fall and loose the honor of their Regiment?

The Valiant , a Leman Russ Vanquisher, as been attached to the 3rd Mechanized Infantry of the same world, and tasked with purging the orks from the world of Agricola Caenum, in conjuntion with the 397th Elysian and the 501st Kreig.

At the moment, it seems a fairly straight forward fight in small towns and cities, as well as the large, fairly open plains. However, in their last battle they discovered the remains of an Elysian platoon that had been gunned down, slain by strangely accurate bolter fire, the sole survivor gasping out 'midnight blue' before expiring…