The pyramid holds four words on one theme — one word per row, split across that row's blocks. Row two might hold DEV and ICE: read along the row and it says DEVICE. The words get longer as the pyramid widens; each row shows its word's length.
Everything is scrambled. Drag letters to rearrange them inside a block, drop one onto a block's felt to move it there (blocks hold two to five letters — never fewer), or drop it onto another letter to swap the two — the letter lights up gold when a swap is about to happen, and a gold line shows where a moved letter will land. Drops are forgiving: whatever is highlighted is what happens. Drag one block onto another to swap them wholesale — including between rows; the block you're carrying hovers over its target. A row locks gold the moment it reads correctly.
Stuck? A hint (+20s, up to five) reveals the next letter of the highest unsolved row. Switch to Timed if you want the clock running.