In Task Builder 2, we have recently added several components for adjusting the difficulty of a task. Change Difficulty Spreadsheet, which allows you to switch to a different spreadsheet, and Change Difficulty Staircase. The latter allows you to adjust a number of task variables under different conditions to control the difficulty of the task!

You can find out more about the new Task Builder here: https://support.gorilla.sc/support/tools/task-builder-2