Maven (Scrabble) on Scrabble. The problem with Alpha Beta is that some Scrabble endgames require 14 moves to play out, and it is not possible to search that deeply. This is not merely a theoretical possibility. When one player is "stuck" with a tile, then playing out all remaining tiles is impossible. In that situation the optimal strategy for both sides is usually to play one tile on each turn. Maven uses a different approach. The B* search algorithm is a selective-depth, progressive-widening algorithm that guarantees to find optimal solutions to two-player games when one can compute upper and lower bounds on
Tile tracking player who can plan and calculate the best move while taking into consideration the other player's possible responses—winning a close game by blocking an opponent’s big play or setting up a high-scoring play the opponent cannot block. Scrabble champion John Holgate notes that tile-tracking is particularly important in tight "bobbing" finishes when the bag is empty, and that many games are lost through "just not knowing what tiles your opponent has on her rack. You simply cannot calculate possible permutations if you are unsure about which letters are relevant." Tracking can also tell a player if the bag is ‘vowel-heavy’