From Hard Drop Tetris Wiki
Glacier is an opening setup with the pattern of TSS→TSD→DT Cannon or Perfect Clear. It has 75.79% chance of Perfect Clear with 8 lines. This setup is discovered and named by a Taiwanese player Octupus Tea. It is named after its resemblance of a glacier trough after the first bag.
Glacier works the best with early J and L.
The setup rate is 37.78% (1904/5040) when counting both orientations.
The second bag can always be stacked like this.
The third bag can be a DT Cannon. One can also freestyle.
O→I and L→J
Additional setups and continuations
Third bag Perfect Clear (8 lines)
- 75.79% PC rate, 34 minimal solutions
However, it is not recommended to take the 8-line Perfect Clear, as there are 34 minimal solutions, and the highest PC chance of a single solution is under 20%.