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Dinosaur Sudoku: Two Dinosaurs and the World They Lived In
Dinosaur Sudoku is classic Sudoku solved with nine prehistoric tiles — T-Rex, sauropod, egg, fossil, volcano, footprint, fern, meteor, and rock. Run it with pictures, with digits, or with numbered pictures; the rule is the same either way: each tile once in every row, column, and box.
Why there are only two actual dinosaurs on the board
Here is the honest design story: the standard emoji set gives us exactly two dinosaurs — a T-Rex and a sauropod — and nine nearly identical lizards would have made a terrible Sudoku anyway. So the set is built as a prehistoric scene instead: the two stars, their egg and footprint, the volcano and meteor that ended the story, and the fossil, fern, and rock left behind. In our experience the resident dinosaur expert at your table accepts this trade instantly, and will also inform you, correctly, that the sauropod is not a brontosaurus.
The meteor arrives last
Tiles join the board in order as it grows. A 4x4 puzzle is the T-Rex, sauropod, egg, and fossil; the volcano and footprint erupt onto the 6x6; and the fern, meteor, and rock only appear on the full 9x9 — which means, fittingly, the meteor turns up right at the end. The pair to watch on the big board is the fossil and the rock, two grey lumps at phone size. They never share a board below 9x9, and if they still blur together there, the Both display mode prints a small number on every tile so the two can never be confused.
Put your expert to work
Dinosaur-mad children usually know more about the theme than the adult they are playing with, and that reversal is worth using. Hand the expert the scanning job: which tiles are already in this row, which box still needs its egg, where can the T-Rex still legally roam. Being the authority on the board keeps a young solver in the chair far longer than being taught — and every one of those questions is real Sudoku deduction.
Whatever the tiles show, the logic is unchanged: every puzzle has exactly one solution, and no tile repeats in any row, column, or box.
After the dig
For the field guide to difficulty grading and hints — and every other board worth digging into — see the Themed Sudoku page.
Dinosaur Sudoku FAQ
Standard emoji only include two dinosaurs — the T-Rex and the sauropod — and nine near-identical lizards would be hard to tell apart anyway. So the set is a prehistoric scene: the two dinosaurs plus their egg, footprint, fossil, volcano, fern, meteor, and rock.
Only on the full 9x9 board. Tiles join in order as the board grows: a 4x4 uses the T-Rex, sauropod, egg, and fossil; the volcano and footprint arrive at 6x6; and the fern, meteor, and rock complete the 9x9.
Yes. The display selector offers pictures, numbers, or both. Both mode is handy on the 9x9, where the fossil and the rock — two grey lumps at phone size — each get a number label that keeps them apart.