The game ran for seven turns and the Tau player and I didn't drop in until the fifth turn due to space constraints and to allow players unfamiliar with the scenario and its special rules a few turns of exploration first before we'd hop in and well, do mean things.

The table in all its glory.

Three of the Tempestus Scions that also took part in the action. Sadly the player had to leave early.

The Tau! Crisis Suits in particular are amazing in Zone Mortalis, being able to quickly traverse the corridors with their jetpacks.

A nice brain bug.
Whenever a door was opened the GM would roll to see what would pop up. Would it be the artefact, or would it be a stasis field holding something? Well..

Behind door number one there was a Carnifex.

Behind door number two there were smaller critters.

Behind door number three.. Orks!

Due to poor positioning the Scions were not doing much for most of the game the player was present, until the Space Wolf player decided to head into his neck of the woods. "HA! S3 weapons aren't scary at all!" Well, how about S3 AP3 weapons with Preferred Enemy? 4laugh

Around the fifth turn both the Tau and my own Solar Auxilia were allowed to hop in.

My first wave of troops rolling into the fray. A Cyclops (armed with an atomic imploder) and a squad of Auxilia flamers, who would go on to scorch quite a few plague marines before being beaten into a pulp. The Cyclops managed to survive two lascannon shots before happily parking itself at the feet of the surviving Obliterator, taking it out in a nice super-nuclear flash. Best 120 pts spent, ever!

And here's my Rogue Trader, with the remainder of her personal guard, locked in combat with a Tau Crisis Suit commander. The combat was hilariously ineffective on both sides, with most of my models unable to wound the fish (Toughness 5, 2+ save) and the fish unable to do much against us due to a low, low WS and a lack of power weapons. In the end the blue coward used Hit and Run to well, run away.
Sadly, in the end our late arrival did little to tip the balance and the Chaos player managed to secure the orb before running off cackling madly.
It was however a fun scenario and I'm looking forward to playing it again later this year.