This trainer shows a partial 3D F2L case. Several algorithms solve the visible front-right pair, but only some of them preserve a free pair in another slot. Your job is to pick one of those algorithms.

The settings modal lets you manage presets, case rows, algorithm columns, per-column colors, and keybinds. Built-in presets are read-only. Custom presets can be edited, extended, and deleted.

Rows with only one valid algorithm are ignored when the trainer starts, because there is no decision to make. If every row gets ignored, the trainer stays disabled until your preset has at least one case with multiple distinct solutions.

History cards can be opened for review. The modal player loads the exact same setup so you can replay each algorithm and study why it does or does not leave a free pair.