A few friends and I recently picked this up, having played and enjoyed Arkham Horror and Eldritch Horror. We played a few scenarios at random and then for our third game we chose Inner Sanctum.
Not sure which options the keeper picked exactly, but with 4 of us against him, he was able to spawn an large number of cultists every turn. Then, of course, he sacrificed them every other turn for Shoggoths. So 4 rounds in, we have 2 Shoggoths on the board, more cultists pouring in and being killed for Hounds of Tindalos, and all of it being fed slowly through the board's chokepoint in the center. At one point I had to pass 6 Horror checks in a row.
I expected this game to be hard but I mean this seems a little ridiculous. Our keeper claimed he "felt bad" for us, which may be true as he never played any Mythos or Trauma cards, but he then continued to annihilate us with his Eldritch monstrocities.
We tried to keep our spirits up by joking around and "going out in style," but after 40 minutes of being stuck in the same room, fighting an endless onslaught we just lost the will to keep playing. Eventually the event deck ran out and everyone lost but the only consolation was that it was finally over.
Sorry for ranting, but is it like this for everyone? Are all the scenarios supposed to be like this, or did we just find a particularly broken set of scenario choices? It seems people have very wildly different opinions on Inner Sanctum, but I just don't see how it's feasible for the investigators to win when the Keeper can so effortlessly send waves of minions at the other players.