Depth-4 search and long outcomes

Judges moves over 25-step continuations, then tries to retain only choices that survive the longer view.

Lifetime objective

Judge a move by how much longer the game will still last, rather than by how many points it scores right now.

N-tuple networks and learning from play

Learn what makes a Drop7 board good from small cell patterns and millions of self-play games.

Value and policy learning

Instead of searching ahead, train a model on past games to judge a board or pick a column, and learn why that kept failing.