If you are stuck! There is a solution-

If you have a town portal, try opening it and going through if you can -
However, if that doesn't work, I have a handy console command we can enable for you. You can 'ascend' a floor ( which will NOT mark you as a cheater ), and that should get you out.

From start->run

%appdata%

and press enter

Then browse to runic games\torchlight
there should be a settings.txt file in there

change
Console :0

to

Console :1

Now, when you load your character, hold SHIFT and press the ~ key
a console should come up -
type ASCEND and press return
that should pop you up a level and hopefully you should be un-stuck.

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