The plan was for them to realize they were losing and have to resort to some nasty alternative strategies. There were 120 savage orcs, mostly with melee weapons, but some salvaged grenades and guns.
The party is at the end of a massive descent shaft (2km long hallway of stone about 10m wide and high). At the end of the shaft is a stone wall with a single doorway. They're on the other side of the doorway, in a tomb.
Setup : They lined up the 3 gunners at the back of the room (medic, operator, heavy) behind cover and put the commissar and priest on either side of the doorway (inside) with their chainswords. The Operator rigged 5 salvaged las carbines to short circuit and eventually explode in the hallway (basically unreliable timed grenades).
I saw that they were determined and not looking for alternatives. I decided we needed an ork counter. I set it to 120. I didn't handle combat with individual attacks, but rather in waves.
Wave 1 : The orks start to close the distance, so a long time of the three gunners opening fire with no distractions. Each player got a BS+60 test with kills-per-degree appropriate to their weapons. The heavy alone killed 30 orks. I was starting to sweat.
Wave 2 : Orks reach the wall. Similar to the previous round but less time so fewer kills. A grenade was thrown at the party. The Priest picked it up to throw back, but botched his agility test. 8 critical explosive damage to the arm. The arm was destroyed, and he would have been dead but for burning a fate point.
Before wave 3 the medic got the priest back on his feet with all the stim and drugs they had. In his drug and fury addled haze he took up his chain-sword in the off-hand and resumed his post (with substantial penalties).
Wave 3 : Orks charge through the doorway. The commissar/priest had to kill them as quickly as possible in order to maximize the amount of time the rear gunners could spend shooting. They killed the orks very fast and the rear gunners killed a lot of orks. One of the Operator's traps takes out about 5 orks. The ork counter is at about 55.
Wave 4 : Same as wave 3, but more orks coming in the door. The **** priest is just using "All Out Attack" to make up for being basically dead. So he can't parry, but it never mattered because he either killed the orks or they missed. He rolled righteous fury about 3 times throughout the battle which gave the players extra fate points. The door guards take a long time, so the rear gunners kill fewer orks. None of the operator's traps detonate. A grenade lands in the back of the room next to the group's grenade/ammo stash, but the operator kicks it away.
Wave 5 : As wave 4, but a Weirdboy blows open the player's left wall and more orks break through. The commissar and priest are both starting to get overwhelmed and one of the gunners elects to focus on keeping orks off of them rather than shooting into the mass (fewer kills, but probably saved the mission). Commisar is badly wounded and the priest still won't die for some reason (he's been at critical damage 8 this whole time). None of the operator's traps explode.
Wave 6 : More orks charge through and the commissar and priest are in dire straights. I think commissar ends the battle with 2 points of critical damage on him and his chainsword is practically jammed-full of ork guts. There's practically no shooting into the hallway from the rear gunners this turn as they're stuck assisting the melee. Luckily about 3 of the operator's traps go off and take about a dozen greenskins down. The weirdboy blasts a few party members with psychic force. At the end of this the ork counter is at 6.
Ending Sequence : They heavy essentially turns the weirdboy and the last few orks into red mist. The commissar moves to step into the hallway, but the operator holds him back. The operator's 5th trap explodes harming no one, and THEN the commissar steps into the hallway.
Anyways, it was great because everyone literally saved the entire party at least once. That Ministorum priest is still recovering from his injuries, but he's going to end up decorated and getting a bad-ass bionic arm.
Since the players took my plan for the adventure and threw it out the window, blew everything up and killed over 100 orks, I had to reward them with XP and fate points.
Edited by eriktheguy