10x10 Winter Gems

Same core idea as the block-fitting genre it borrows from - drop shapes onto a board and clear straight lines - but slowed down since nothing forces a move before you're ready. The Christmas gem skin is mostly cosmetic, though it does make full-line clears feel a little more festive than plain blocks would. As the board fills up, the margin for a bad placement shrinks fast, so late-game boards get tense even without a clock running.