Card Sudoku

Card Sudoku is a logic puzzle for sports card collectors. You have a 4x4 grid and must place cards from 4 sports (MLB, NBA, NFL, NHL) so that each row and column contains exactly one card from each sport. Some cells are pre-filled as clues — use logic to figure out the rest.

First, select a sport from the palette at the top (baseball, basketball, football, or hockey). Then click any empty cell to place that sport there. If the placement is wrong for that cell, it will flash red. Double-click a non-clue cell to clear your placement.

Instead of numbers 1-9 in a 9x9 grid, Card Sudoku uses real sports cards from 4 sports in a 4x4 grid. Each card shows a real player from the CardVault database. The constraint is the same — each row and column must have exactly one of each type.

Yes, the Daily Challenge generates the same puzzle for all players based on the date. Compare strategies with friends! Random mode generates a unique puzzle each time for unlimited practice.

Clue cells are pre-filled cards that cannot be changed. They show a sport icon, player name, and a "clue" label. Use these locked cells as starting points to logically deduce which sports go in the remaining empty cells.