Worry not! There is some awesome news for the future of Thief Simulator!
Not only are we working on the paid DLC but we will release a big patch 1.7 along it.
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What will be added in the 1.7 free patch:
-new lockpicking tool
-improved graphics and animations
-new location: farm
-tractors to steal
We need a bit more time to finish all that content. Thank you for your patience.