In our gaming session last night, I made a call that was controversial, and I'm pretty sure I made the wrong call. I could really use some feedback from the GMing community.
Here's the setup:
I'm running my players through the AoR "Dead in the Water" adventure from the GM screen, and we've been going through it for four sessions now. We're getting to the endgame, and currently the group is split up, trying desperately to save the Nebulon-B frigate from getting sucked into a black hole. The frigate gets to the event horizon at event counter 10, and it was at 7 when we started the game. Our big game hunter/resident Force-user is trying to clear out the aft hangar bay by herself and having a rough time of it. Our thief/assassin and our doctor/melee fighter are trying to restore power to the engines. Our mercenary captain and scoundrel are trying to take the bridge with a squadron of soldiers. Events are getting heated.
The doctor rolled a Triumph and some on his melee attack, and I figured that the Triumph would let him know the secret about the static vane and how to ionize the droids. They knock out the droids, and now they have to get the engines started. According to the adventure, starting the engines requires a Daunting Computers check and a Hard Mechanics check. Against all odds, the thief and the doctor make the Computers check, and then it's time for the Mechanics check. They fail, but with two Advantage.
The doctor says, "So, for the two advantage, could we say that the repair was made, but there is some other part that has to be fixed as well?" It strikes me as a reasonable request, so I agree to it. In retrospect, it might not have been the greatest decision ever, but I think it works well with what is going on. I say that the component that needs to be fixed is located in a maintenance shaft. The thief has the higher coordination, so she goes in. At this point I'm thinking it's going to be an Average Mechanics check. I've spent a Destiny point on the Daunting computers check, so I'm thinking this is going to be a good place to stop for the night.
The thief fails the check. No Advantage, no Threat--just a failure.
The controversy:
The thief asks if she can try again. Here's where things start to get complicated for me. If there was some other symbols out there, I would probably have had a bit more of a guideline to follow. Still, there's just nothing, so I figure it's reasonable for the thief to try again. Nothing indicates the repair was impossible to make. She rolls again and gets a failure with two Threat. I say that she fails, and what's more she can't try again.
Then the doctor says, "Okay, I'm going to go in there and try to fix it." At this point I'm wondering if I should just say the engine can't be repaired, but I also know that if the engine isn't repaired, there is going to be a lot of NPC deaths, and the game is going to get very dark very quickly. I don't know that I can refuse, but I'm also wondering how many chances the PCs deserve. I say that he can do it for a Destiny point. I throw a couple more Destiny points at the doctor and increase the difficulty of the Mechanics roll, but he pulls it off, and with one Advantage, too.
I end the session saying that the ship's engines have been repaired, but the bridge hasn't been taken back yet, and that the heroes have all of five minutes before they fall into the event horizon, to account for the multiple attempts to start the engine.
I'm wondering if I made the right call in having the group take so many shots at restarting the engine. I was thinking what I should have done was said that particular engine couldn't be repaired and have the PCs try to get to a different engine's computer systems and attempt the same checks again. The way I did it I feel as though there were no penalties for failure, and that's not the feeling I want to give my adventures. Having said that, I don't want a major point of the adventure to get torpedoed by a bad dice roll.
I would love to hear what other GMs thought about my decision, and whether they would have done things differently.