OK, here is what happened:
Having told them there was maybe another half hour left to the LSS duration, I noted the time on my watch.
It took them a while to open the windows and look around, and even then, they just started with one window (the “wrong” one). Eventually they opened the other window and saw the one giant standing about 60’ away. The paladin detected evil (and found it) on the giant. They heard another one behind the shelter.
They debated and discussed the situation for a long time. They eventually let the archer take a shot at the giant they could see, but that just ticked off the giant and brought him up to the shelter where the archer and sorcerer couldn’t target him without revealing themselves for attack (which the sorcerer did, once, to cast evard’s black tentacles – not real useful against giants).
They considered just teleporting out. They had no need or reason to fight the giants. Heck, their whole plan for the day was to teleport back to their base city anyway. The amazing thing here was really a normal thing for this group – they just discussed everything without actually making a plan or taking an action.
The sorcerer had suggested they just teleport out. The paladin dismissed his dire wolf because the sorcerer couldn’t take it with them (Large creatures count for two in the teleport). Then they started to discuss their options again.
I looked at my watch; 40 minutes had passed since I told them 30 minutes remained of the LSS. The sorcerer said, “I’ll just teleport us out,” and moved his mini to be between the two other PCs.
Because I had given them more than appropriate time for their decision, I told the sorcerer to roll initiative, as the LSS was about to end. The initiative was for what happened first, his teleport or the LSS ending.
He won initiative. And then the group again started discussing the topic. They talked it out for another 20 seconds or so before I stopped them and said, “The shelter ends.”
Now they were standing in the middle of the desert with two giants, with reach, on either side of them (and with no dire wolf). We all rolled initiative and the battle began. They were brutalized by the giants before they managed to teleport out. I could have killed them had I taken every AoO and made all the giant’s attacks (I only did a full attack once, even though they could have taken such every round.)
So, what I thought would be a challenging fight, but with the PCs having a tactical and initiative advantage (they could choose how and when to exit the shelter), turned into a TPK that only failed to happen because I pulled the punches.
They even commented afterwards that they set up the surrounded tactical disadvantage themselves.
I asked this question here because I wanted to see if the set up was just truly overpowering and killer, or if it was within realistic realms for these characters. I thought with the tactical situation totally in their hands, they could handle it. I was surprised at how that advantage was let go.
Quasqueton