You're developing the core algorithm for a next-generation word puzzle game that combines elements of Scrabble and Diablo. The game is played on a single grid where players swipe to form words from adjacent cells. The Challenge: Your game engine needs to process thousands of concurrent games with grids up to 20x20 and dictionaries containing 100,000+ words. A naive solution that checks every possible path would create unacceptable server load and timeout issues.

By connecting adjacent cells (8-directional movement), each cell can only be used once per word path.