Where the points actually come from

Before trying to score more, this work simply asked where the points already come from — and the answer turned out to be that a Drop7 Hardcore score is survival time wearing a different unit.

This is not a policy. It is a measuring instrument: it plays the existing reference policy, unmodified, and counts things while it plays.

The intuition

There are three ways to earn points in this game mode, and they are wildly unequal in size.

Chains are what a human player experiences as playing well. The scoreboard barely notices them. Staying alive one more rise is worth more than almost any chain you can build, and the rises arrive on a clock you do not control. So the question "how do I score a million points?" collapses into "how do I stay alive roughly three times longer?"

How the measurement works

1. Input. Nothing new. The program includes the frozen reference searches — the depth-3 and depth-4 fair expectimax policies — as a library and calls them unchanged.
2. Instrumentation. A wrapper around the game loop tags every point earned as one of three sources: the flat bonus for surviving a row rise, the 70,000-point bonus for emptying the board, and the points paid for each wave of a chain.
3. A self-check on every game. The three sources must add up to the engine's own score exactly. The run aborts if they ever do not.
4. Weak controls. Three deliberately bad policies — always the centre column, a random legal column, and always the shortest column — play the same games, so the value of searching can be separated from the value of merely being alive.
5. Output. Per-game records: score, moves, rises, board clears, the three point sources, how many numbered discs were cleared and how many gray discs were revealed per move.

What it found

Over 64 fresh games of the reference policy, score and lifetime were essentially the same variable — the correlation between a game's final score and the number of moves it lasted was 0.9995. Row-rise bonuses supplied 94.29% of all points; chains supplied 5.71%; emptying the board supplied nothing at all, because it never happened.

The second half of the finding is an arithmetic constraint rather than a measurement. Every five-move cycle puts 12 new discs onto a 49-cell board: the 5 you drop, plus the 7 that arrive underneath on the rise. To survive indefinitely, a policy must therefore average 2.400 numbered clears and 1.400 gray-disc reveals per move. The reference policy sustains 1.973 and 1.090 — a deficit of roughly 18% and 22%. It is not dying of bad tactics; it is running a slow, structural shortfall, and the games that last longest are exactly the ones that come closest to closing it.

What this taught us, and what is still open

The useful consequence is a change of target. The repository's own research status had described "roughly 2.4 numbered clears and 1.4 reveals per move" as an empirical region associated with long games, with a warning that they were diagnostic targets rather than proven thresholds. They are neither empirical nor approximate: they are 12 divided by 5 and 7 divided by 5, the exact disc-conservation requirement of the five-move rise cadence on a 49-cell board.

It also gives learning experiments a better label to predict. Raw score is a heavy-tailed variable quantised in 17,000-point steps, with one number per game. Remaining lifetime is the same quantity without the tail or the quantisation, and per-move clear and reveal counts give one labelled observation per move instead of one per game. That reasoning is what the survival-hazard evaluator was built on.

And it bounds what search alone can do. Rises come every five moves, so a four-move look-ahead sees at most one rise boundary and cannot observe a flow deficit accumulating across the forty-odd cycles that separate a 94-move game from a 294-move one. The deficit is a slow variable, and a fast search is the wrong instrument for it.

Still open: whether a policy that deliberately hunts board clears could change the arithmetic. At 70,000 points a clear is worth 20.6 moves of survival, so one clear per 20 moves would double the points-per-move rate. Nothing here measured whether that is reachable.