Kneel Before Glorak: A sudoku trying to lord over us!

Today's Video:

Fascinating puzzle from Gnubeutel. I suspect there are smoother solves out there though!

Link to Play:

Kneel before Glorak by Gnubeutel https://tinyurl.com/SudokuSleuthKneelBeforeGlorak

Rules:

Normal Sudoku rules apply.

Extra Region: cells shaded gray form an extra region made up of the digits 1-9.

Thermometer: digits on a thermometer increase from the bulb end.

Killer Cages: digits in cages may not repeat and sum to the number in the top left corner of the cage.

Diagonals: digits may not repeat on each main diagonal.