Arcade Lab controls, settings, and diagnostics#

Arcade Lab has one game that is actually being played and, depending on the algorithm, a crowd of candidate games under consideration. A walker is a complete emulator snapshot: its memory, its reward history, and the small piece of game-specific bookkeeping needed to continue from that exact moment. It is a complete state, far richer than a dot wandering over a map.

This distinction is the key to the whole page. Wave and Graph display a leading search walker. FMC and Jump Wave display the one committed game, while their walkers search possible continuations in the background. The planner may spend a long time examining futures while the committed game holds its current frame. Then it chooses an action or path, plays it, and searches again from the new emulator state. See Arcade Lab for the broad picture and Arcade Lab environments for game-specific state and reward details.

Question

Read this control or display

Which future is being copied?

Virtual reward, the cloning signal; Cumulative reward measures game progress.

What is actually on the screen?

Best walker for Wave/Graph; Played game for FMC/Jump Wave.

How many game copies act now?

Walkers (N) for Wave and the planners; Graph uses it as starting walkers and minimum leaves.

How large may the Graph become?

Max walkers, its cap on retained emulator-state nodes.

Did the game really run this many frames?

Env frames, the exact count returned by the emulator steps.

Choose an algorithm#

The four buttons are four ways of spending the same basic resource: complete game continuations. The action vocabulary is discrete, and an action is held for several emulator frames. The interesting part is what happens after the population has produced a mixture of good, bad, diverse, and dead timelines.

Wave keeps a fixed population. Every walker samples an action, holds it for its sampled dt, and steps. The cloning operation then copies promising timelines onto less promising ones. This is the simplest view of the Fractal Gas: a fixed crowd of alternative plays.

Graph keeps the history instead of overwriting it. A visited emulator state becomes a node, and the active leaves are the states from which new alternatives can be extended. Each graph update steps the leaves selected for cloning; the tree can therefore grow while the number of active leaves remains near the requested minimum. Each node retains a full emulator state, which is why its memory cost is much larger than a single dot suggests.

FMC and Jump Wave use an ArcadePlanner. They search from the current committed game while keeping candidate states as search snapshots. FMC chooses the most represented first action among surviving search branches, then advances the committed game by that one action and replans. Jump Wave can execute a common initial path shared by the surviving branches, or the entire winning branch when its consensus option is cleared. In both cases, the bright game view is the committed emulator, distinct from the best search snapshot.

Algorithm

Population meaning

What is committed to the played game?

Special readout

Wave

Fixed N walkers; all act each iteration.

Wave displays the leading search walker; its state stays in the search population.

Best walker screen and swarm plots.

Graph

N initial walkers and minimum leaves; nodes grow up to Max walkers.

Graph displays the leading search walker; its state stays in the search population.

Nodes / leaves / stepped, plus parent lines on the map.

FMC

Search population of N candidate continuations.

One voted first action, then replan.

Played game, search depth, played score, and played frames.

Jump Wave

Search population of N candidate continuations.

Shared prefix by default; full best path or a fallback under the rules below.

Same planner readouts, with the current execution mode.

Separation of a committed arcade game from candidate search walkers and selected actions.

Fig. 39 The planner’s search population branches from a frozen committed game, then sends the selected action or path alone back to the game being played.#

Here is the picture to keep in mind for a planner. Put one emulator on the table—the committed game—and make copies of it for an experiment. The copies may run ahead, die, discover a useful route, or disagree about the next button. Those copies leave the emulator on the table unchanged. After the planner selects an executable action sequence, the committed game advances.

This is why Max reward can rise while the displayed Sonic or Mario screen holds steady during several search iterations. The search is making progress in possible futures. The separate Played frames counter moves when the committed game executes an action. A search result can also be good and remain unselected: the planner applies the full algorithmic selection rule with the population context.

Planner settings#

The Planning section appears for FMC and Jump Wave. Search horizon is the normal number of search iterations before a decision can be made. An iteration samples and executes one action per active search walker, so the horizon is a depth in action edges; the actual time covered by an edge depends on its sampled dt.

FMC uses the population at the normal horizon to vote on its next action. Jump Wave’s checked Stop at first bifurcation setting means “execute the exact ancestral prefix shared by the surviving final walkers.” If they disagree at the first edge, the shared prefix is empty, so Jump Wave keeps searching. A single surviving branch shares its path with itself; shared-prefix agreement means identical ancestry among the surviving branches.

Maximum search horizon matters only for Jump Wave while that checkbox is checked. 0 means twice the normal horizon, capped at 4096. An explicit value must be at least the normal horizon. If the search reaches that limit before a shared prefix appears, the implementation falls back to one positive-duration action from the best available branch. If all search walkers are dead, it likewise uses a one-action best-path fallback when a path exists. With the checkbox cleared, Jump Wave executes the selected best branch’s full recorded path. Each selected action still needs an execution step; the browser callback advances along a long path one action at a time.

Setting

Browser default and UI range

Applies to

Change behavior

Search horizon

32; integer 14096

FMC and Jump Wave

Live; discards the pending search/plan and starts planning from the current committed game.

Stop at first bifurcation

Checked

Jump Wave only

Live; the checked state uses the shared prefix, and a cleared checkbox uses the full selected best path.

Maximum search horizon

0 (automatic); integer 04096

Jump Wave with the checkbox checked

Live; nonzero values must be at least Search horizon.

Note

Changing a planner setting preserves the current game. It invalidates the queued search or trajectory and replans from the current committed emulator. A change to the console, start level, algorithm, observation mode, walker count, Graph cap, or seed does rebuild the run.

Choose RAM, RGB, Gray, or Coords#

The observation is what the algorithm uses when it asks whether two walkers are far apart. It can differ from the human view and from the reward signal. RAM exposes emulator memory. RGB exposes screen pixels with three values per pixel. Gray reduces the screen to one luminance value per pixel. Coords is a hand-written compact state representation for the games where the implementation knows useful coordinates.

Coords is a compact, hand-written state representation. It compares the pieces of state that matter for reachability: position, momentum, room, level, or other game variables. Mario, Sonic, and dedicated Montezuma default to it; generic Atari defaults to RAM because each Atari ROM has its own state layout. In generic Atari, selecting Coords deliberately aliases RAM.

Changing the observation mode restarts the run because it changes the vector used for distance and the state representation allocated to every walker. RGB and Gray can be useful experiments, but their large vectors make the same population much more expensive than Coords.

Console

Default

RAM

RGB / Gray

Coords

Mario / NES

Coords

2048 values

256×240×3 / 256×240

10 raw values: position, vertical state, level identifiers, time, velocities, sub-area, and power-up.

Generic Atari / ALE

RAM

128 values

Dimensions reported by ALE; the common frame is 160×210

Same 128-value RAM vector supplies the state representation.

Sonic / Genesis

Coords

65536 values (64 KiB work RAM)

320×224×3 / 320×224

6 scaled values: position, velocities, ground speed, and zone/act progress.

Montezuma / dedicated ALE

Coords

128 values

160×210×3 / 160×210

8 raw values: pyramid-global position, room, local position, level, inventory bitmask, and lives.

The table contains an easy trap. A pixel observation is large because the machine has many pixels; the observation itself carries pixels, while interpretation requires a separate model or adapter. A Coords observation is small because the adapter has selected a few RAM-derived variables. The reward adapter still runs separately. Coords keeps score and distance as separate signals, and RGB supplies screen pixels as the observation; learned visual recognition requires a model that uses those pixels.

The exact tuple contents are documented in Arcade Lab environments. There, the Mario identifiers are described as raw NES values, Sonic’s first five quantities are scaled by 256, and Montezuma’s global coordinates place local room positions into the 24-room pyramid. Those details matter when interpreting a distance coefficient: the units are representation-dependent.

Set the swarm and Graph population#

The browser-facing default is Walkers (N) = 48, with an integer range from 2 to 1024. In Wave, FMC, and Jump Wave this is the number of complete game copies in the current search population. In Graph, the same input is relabeled Leaves (start = min leaves): it supplies the starting walkers and the minimum number of active leaves the tree tries to maintain.

Graph has another number because its history is retained. Max walkers is a cap on graph nodes, including currently stepping leaves. The UI chooses a console-specific default: Mario 4000, generic Atari 20000, Sonic 150, and dedicated Montezuma 20000. The input range is 2100000, but the effective cap may be lower when browser WebAssembly memory reaches its capacity for another full emulator state. The ready message reports that effective cap. Sonic’s smaller default is intentional: Genesis state blobs are comparatively expensive.

Seed defaults to 7. It drives random action choices, frame skips, and clone decisions. It is applied when the run is built, so changing it restarts the run. Elite walkers defaults to 2, accepts 016, and is hidden for Graph. In Wave, FMC, and Jump Wave, the best walkers ever found by cumulative reward are kept in an elite buffer and re-injected on later iterations. Set it to zero to disable that buffer. Graph exposes its best state through the retained tree, with its elite state represented there.

Setting

Default and range

Meaning

Change behavior

Walkers (N) / Graph Leaves

48; integer 21024

Wave/planner population, or Graph starting walkers and minimum leaves.

Restart required.

Max walkers

Mario 4000, Atari 20000, Sonic 150, Montezuma 20000; integer 2100000

Graph’s maximum retained nodes; the effective value may be memory-capped.

Restart required; Graph only.

Seed

7; nonnegative integer

Random actions, inclusive frame skips, and cloning choices.

Restart required.

Elite walkers

2; integer 016

Best-ever cumulative-reward walkers re-injected by Wave/FMC/Jump Wave. 0 disables.

Live for those three algorithms; the next iteration uses the new count.

Graph also offers Freeze shared prefix after N nodes, an integer from 0 to 100000 that requires a restart. At 0, Graph behaves as before. At a positive value, a path shared by alive continuations is archived once at least N nodes lie between the active root and the first branching point. The branching point becomes the new active root. Archived nodes no longer count toward Max walkers or participate in cloning, but their states and parent links remain stored and appear green on the map.

Understand fitness and visit controls#

There are two meters in this experiment. The environment produces a cumulative reward: game score for generic Atari, and shaped game progress for Mario, Sonic, and dedicated Montezuma. The cloning operation combines that number with other signals to build a virtual reward, the selection signal that says which timeline should be copied.

In the current implementation the virtual reward is a product of population- rescaled factors:

[ V = D^{a},R^{b},Q^{c}. ]

D is observation distance from a randomly chosen companion, R is the cumulative reward signal, and Q is the visit factor when visit reward is on. The coefficients are the exponents Distance coef a, Reward coef b, and Visit coef c; each defaults to 1, has range 03, and moves in steps of 0.05. The backend rescales each current population signal before forming the product, so these exponents act on population-rescaled signals. Raw pixel distances and raw score units pass through that rescaling before exponentiation. A zero coefficient removes that factor’s variation. Higher Distance coef favors diversity, higher Reward coef favors accumulated progress, and higher Visit coef favors the exploration signal.

The rescaling is asymmetric: a signal with zero spread contributes the neutral factor 1; standardized values above and below the population mean are mapped differently. This is why a virtual reward can change when the population’s spread changes while the underlying game score stays fixed. A low-fitness walker can be cloned onto a higher-fitness companion, and dead walkers are always eligible to clone. Read Virtual reward as “what the resampler preferred,” and Cumulative reward as “what the game scored.”

Control

Default and range

Applicability and meaning

Change behavior

Distance coef

1.00; 03, step 0.05

Exponent on rescaled observation distance; higher values preserve diversity.

Live.

Reward coef

1.00; 03, step 0.05

Exponent on rescaled cumulative environment reward; higher values exploit progress.

Live.

Visit coef

1.00; 03, step 0.05

Exponent on the visit factor, when visit reward is enabled and visit controls are available.

Live.

Visit reward, pooling, and erasure#

Visit controls are specific to Coords on Mario, Sonic, and dedicated Montezuma. The implementation maintains visit counts while their reward term is inactive. That makes a useful ablation possible: set the term to Off while history continues accumulating, then turn it back on with the earlier visits preserved.

Visit reward is On by default for Graph and Off by default for Wave, FMC, and Jump Wave. On means that walkers in less-visited coordinate cells receive a larger visit factor in virtual reward. Off makes the visit factor neutral; the counters remain intact. Visit pooling (px) defaults to 5, with range 11024. The backend stores counts at the underlying pixel/key resolution but sums a square B×B window, where B is the pooling value, before using the count in fitness or the heatmap. A larger window makes novelty coarser; the per-pixel history remains intact when this setting changes.

Erase coef defaults to 0.05, with range 01 in steps of 0.01. At each iteration stored counts decay by this coefficient. Zero preserves stored counts indefinitely; a larger coefficient lets old exploration become novel again more quickly. The visit grid is part of the current run, so Reset clears it. Changing any of these three settings is live. The map’s visits toggle is a display choice and is also remembered by the browser; it asks the worker to send the current blocks while the view is on.

Setting

Browser default and range

What it changes

Visit reward

Graph On; Wave/FMC/Jump Wave Off

Whether visit novelty affects virtual reward. Counts continue in either state.

Visit pooling (px)

5; integer 11024

Side length of the square sum-pooling window for the visit term and heatmap.

Erase coef

0.05; 01, step 0.01

Per-iteration decay of stored visit counts.

Retained Graph state tree, walker leaves, and visit-count heatmap over an arcade level map.

Fig. 40 Graph parent links show the alternatives that were retained, while the heatmap shows the accumulated coordinate visits used by the optional novelty term. The two are related views built from distinct data structures.#

There is a subtle but important separation here. A Graph node is a full emulator state with an ancestry link. A visit cell stores a count attached to a coordinate key. The graph can remember a branch that later becomes dead, while the visit grid can say that a region has been explored many times. Each view offers a partial description of the run, while the committed game in a planner remains a separate state.

Tune the game reward terms#

The Reward terms panel is game-specific. Every slider below is live and changes rewards earned from the next transitions onward. It leaves the cumulative reward already carried by a walker unchanged, so historical plot points and an old elite’s history retain their original meanings. For a planner, changing reward weights also discards the pending search/trajectory and replans from the current committed game; the game continues from its present state.

The words “game reward” need one qualification. Generic Atari passes the ALE score delta through directly. Mario, Sonic, and dedicated Montezuma use the shaped reward adapters below. In every case this is the cumulative environment reward shown by the reward plot, before the virtual-fitness rescaling and coefficients are applied.

Console

Term (UI label)

Default; UI range and step

Applicability and effect

Mario

X progress (x)

1; 05, step 0.1

Signed accepted horizontal progress per pixel. It also scales the shortcut-distance payout when a pipe/warp returns Mario farther along.

Mario

Time penalty (time)

1; 05, step 0.1

Penalty for the in-game clock decreasing. 0 removes time pressure; the flagpole countdown is treated as forward progress.

Mario

Death penalty (death)

25; 0100, step 1

One-off penalty while dying or dead. It is inside the per-frame clip.

Mario

Per-frame clip (clip)

15; 1100, step 1

Clips the combined x, time, and death contribution to plus/minus this value. Flag and area bonuses are added after the clip.

Mario

Flag bonus (flag)

500; 02000, step 10

One-off reward when the flagpole is grabbed. The wrapper remains active after flag capture.

Mario

Area bonus (area)

100; 0500, step 5

One-off reward for the first entry into each pipe, warp, bonus, or intro area in the stage.

Sonic

X progress (dx)

1; 05, step 0.1

Signed horizontal progress. The adapter holds this term at zero while a boss is loaded; the guard filters implausible jumps beyond its range.

Sonic

Rings (rings)

3; 020, step 0.5

Signed ring change: gains reward and lost rings penalize. A hit that drops rings therefore matters.

Sonic

Score (score)

0.5; 05, step 0.1

Multiplier on in-game score changes from enemies, monitors, boss hits, and tallies.

Sonic

Exploration bonus (cell)

500; 02000, step 10

One-off reward for a new 64×64 map cell in a walker’s lineage and current act.

Sonic

Extra-life bonus (life)

1000; 05000, step 50

Reward for gaining a life, including a 1-up or a 100-ring life. Life loss ends that walker; this term rewards life gains.

Sonic

Boss hit bonus (boss)

2000; 010000, step 100

Reward per boss hit point removed; Sonic 1 bosses use eight hit points.

Sonic

Act clear bonus (act)

5000; 020000, step 100

One-off reward when zone/act progress advances. It is outside the Sonic x-distance calculation.

Montezuma

Game score (score)

1; 05, step 0.1

Multiplier on ALE score delta from keys, doors, jewels, enemies, and other game events.

Montezuma

New-room bonus (room)

500; 02000, step 10

One-off reward for entering a new one of the 24 rooms in a lineage on the current temple level. The reward is zero during dying and for terminal room 8.

Generic Atari

ALE score delta only

Uses the selected game’s ALE score delta as its sole reward-term signal; the interface presents the score adapter as its sole reward signal.

The large values are deliberate. Sonic’s act-clear and boss terms are meant to make finishing and fighting visible to the selection signal; Montezuma’s room bonus is meant to keep a lineage exploring. Mario’s clip keeps one ordinary frame’s contribution bounded, while its flag and area events are added after the clip so important transitions retain their full effect.

These weights have console-specific meanings. A value of 500 means something different when it pays for a Mario flag, a Sonic map cell, or a Montezuma room. When comparing runs, record the console, ROM, start level, and the complete reward-term vector.

Set the frame skip: dt min and dt max#

At each walker step, the algorithm chooses one discrete action and holds it for an integer number of emulator frames. dt min defaults to 6; dt max defaults to 30. Both accept integers from 1 to 120, and dt min stays at or below dt max. The implementation samples uniformly, inclusively, between the two endpoints. At roughly 60 frames per second, the defaults mean about 0.1 to 0.5 seconds per sampled action.

This is a control-resolution choice. Smaller values let the swarm change its mind more often but require more iterations to cross a level. Larger values move farther per iteration but make a mistaken button hold harder to undo. A terminal event can end a hold early, so the actual number of frames can fall below the sampled number. In planner mode, the recorded edge duration is used when the action or path is committed.

Both controls are live. A planner setting change invalidates its current search so the next search samples with the new interval; Wave and Graph use the new interval on later iterations. The Mean frame skip (dt) plot reports the mean of the steps that actually ran, and Env frames reports the exact emulator-frame total.

Control

Default; range

Interpretation

dt min

6; integer 1120

Smallest inclusive action hold.

dt max

30; integer 1120

Largest inclusive action hold. Must be at least dt min.

Read the screen, map, plots, and statistics#

The display is a report from the current algorithm; each algorithm defines its own camera. Wave and Graph label the screen Best walker and render the leading search state. FMC and Jump Wave label it Played game and render the committed state. Their plots can still change while that game view is paused, because the search population is doing work elsewhere.

The maps are also implementation-specific. Mario uses a supplied full-level map and overlays the swarm. Sonic’s UI stitches downsampled camera tiles from the walkers, so dark territory marks regions this swarm has yet to visit. Montezuma builds a 24-room pyramid from valid HUD-cropped room frames as walkers enter rooms. Generic Atari presents its screen and plots as its display views; Mario, Sonic, and dedicated Montezuma provide the map views. In every map, magenta dots are alive walkers, gray dots are dead walkers, and the gold ring marks the best walker. Graph draws parent links and larger leaf markers, showing retained ancestry across branches.

The optional visit view changes the base map to grayscale and draws pooled visit blocks with a fire scale. Blocks with zero recorded visits are transparent; walkers remain on top. This count heatmap represents recorded visits; future prediction belongs to a separate model. It can be viewed for any solver that is counting visits in Coords mode, although Graph is the solver for which the visit term is enabled by default.

Display

Meaning

Cumulative reward plot

Max and mean cumulative environment reward. It is shaped game reward for Mario/Sonic/Montezuma and ALE score reward for generic Atari.

Virtual reward plot

Max and mean cloning fitness after distance/reward/visit factors are rescaled and exponentiated; Cumulative reward reports game score/reward.

Cloned walkers (%)

Percentage of the current update population counted as cloned; dead walkers are always clone candidates. High values usually mean stronger concentration on a few timelines.

Alive walkers

Walkers still active after the latest update. Wave and Graph can replace dead walkers by cloning while a live companion exists.

Mean frame skip (dt)

Mean number of frames actually held in the update, normally between dt min and dt max but shortened by terminal events.

Graph size

Graph-only time series of total nodes, leaves, and walkers that stepped.

Iteration

Completed algorithm iterations. Planner execution messages update execution state while the plots retain the current search iteration.

World

Mario/Atari-style world-stage value, Sonic zone abbreviation plus act, or Montezuma room, level, and lives. Planner mode uses the committed game’s location.

Max reward / Mean reward

Highest and average cumulative environment reward in the current reported population.

Alive

Alive count over the current population; Graph’s population can change, so read its displayed denominator to account for the current N.

Nodes

Graph-only nodes / leaves / stepped for the latest update.

Iterations/s

Three-second sliding average of worker step messages; planner search messages contribute, and execution-only messages update execution state separately.

Env frames

Exact total emulator frames actually run since reset, summed over walker steps.

Planner / phase

planning, playing, or ended; identifies whether the committed game is still or executing a selected plan.

Search depth

Current depth of the planner search. It can reset when a decision is committed or when a live planner setting invalidates the pending search.

Played score

The committed emulator’s display score; for games represented through accumulated reward, the adapter reports accumulated reward.

Played frames

Exact frames executed by the committed game, separate from the many search-walker frames.

The two reward plots answer different questions. Cumulative reward asks, “What has this timeline earned under the current game reward adapter?” Virtual reward asks, “How attractive is this timeline to the cloning rule, after the population’s distance, reward, and optional novelty signals have been rescaled?” A swarm can raise virtual reward through diversity while cumulative game reward is flat. Conversely, a high-scoring walker can be cloned away if the current population-level fitness comparison selects other timelines.

Planner plots are sampled on search advances. Executing a selected action updates Played score and Played frames, while the swarm plots retain the current search point. This is why the planner status can say Playing while the plot lines hold still. The screen, the planner counters, and the population plots are three synchronized, distinct views.

Reset, terminal states, and reproducibility#

Start begins the worker loop or resumes it. Pause stops scheduling new steps and preserves the current Wave population, Graph tree, planner search, or partly executed trajectory. Reset rebuilds the active environment with the same selected settings and seed, clears the swarm/tree or planner state, clears visit counts, maps, plots, and readouts, and leaves the run paused. It is the right response to an all-dead stop or a completed committed game.

Wave and Graph stop when every current walker is dead: the population then has zero live companions for useful cloning. A dead walker can be copied while some live walker remains, so the alive plot may dip and recover. A planner is different. Its search population can hit the all-dead fallback while the committed game is still valid; the planner may play one fallback action and search again. The committed game ends when the actual environment reports a hard terminal state.

The game adapters define those terminal events. Mario stops on dying, falling or dead player states, or game over; flag capture leaves this wrapper running. Sonic treats any life loss or zero lives as terminal for that walker. Generic Atari marks life loss as done for the walker and can recover it while lives remain, but game over is hard. Dedicated Montezuma follows the Atari life rule except that entering room 8 is deliberately hard terminal and earns a zero room bonus. An action hold can therefore finish before its sampled dt.

For a reproducible run, write down the ROM identity and build, console and game, Mario World/Stage or Sonic Zone/Act, algorithm, observation mode, walker count, Graph cap, seed, elite count, fitness coefficients, visit settings, reward-term vector, and dt range. For planners also record horizon, consensus, and maximum horizon. The browser derives its parallel worker count from the machine’s hardware concurrency (capped at eight), so include the browser/device when comparing throughput or exact traces.

With the same ROM bytes, WebAssembly build, starting selectors, active settings, and seed, the implementation’s random action, frame-skip, and cloning choices are intended to replay the same experiment. A seed fixes those random choices while wall-clock speed remains a runtime property, and a different browser build, ROM, observation mode, or population changes the sequence of emulator states. A reward-term edit is also a new reward boundary: it affects future transitions and leaves history unchanged.

Setting class

Controls

Restart required

Console/game, Mario World/Stage, Sonic Zone/Act, algorithm, RAM/RGB/Gray/Coords, Walkers (N), Graph Max walkers, and Seed.

Live

Distance/Reward/Visit coefficients, dt min/max, Elite walkers where applicable, Visit reward, pooling, erase, and all visible game reward terms.

Live but replans

Search horizon, Jump Wave consensus, maximum search horizon, and planner reward/fitness changes. The committed game is retained; pending search state is discarded.

Display only

Map zoom/fit, map resize, plots/sidebar layout, and the map visits toggle. The visits toggle is remembered locally by the browser.

Troubleshoot the common surprises#

When the page reports Not cross-origin isolated, the server configuration usually causes the status. Serve the repository’s browser app with fractal-gas-web/serve.py and reload; that app server supplies the headers needed by WebAssembly threads, while direct HTML loading and plain static hosting use response paths that omit those headers. If the status remains on ROM loading, use the permitted local ROM, unlock the encrypted vault, or upload a permitted Sonic ROM. A generic Atari game and the dedicated Montezuma button are separate experiments: choosing Montezuma in the Atari game picker selects the generic Atari experiment; the dedicated Montezuma button supplies the room-aware map and room reward.

If Graph stops at a lower node count than Max walkers, read the effective cap shown beneath that control. Each node stores a complete emulator state, and the browser may cap the request for memory. Lowering the cap or choosing a smaller observation is the relevant fix. The map and visit controls appear with Mario, Sonic, or dedicated Montezuma plus Coords observation; generic Atari uses its RAM state and standard screen and plot views.

If all walkers die, the population has reached a terminal state; rendering continues to report that state. Reset first. For a controlled experiment, lower dt max, reduce a population that is exhausting memory, or inspect the reward terms and terminal game state. If the planner seems to pause, look at Planner and Search depth: a long horizon or Jump Wave’s extension can spend many worker steps planning before any committed action is played. Lower the horizon for a quick diagnostic.

Finally, a dark Sonic map marks unexplored fog; a gray dot marks a dead walker; and a rising Virtual reward signals cloning preference while Cumulative reward tracks game score. These three interpretations account for most apparent contradictions between the screen, map, and plots.

Warning

Compare cumulative-reward magnitudes across Mario, Sonic, generic Atari, and Montezuma alongside the reward adapter and slider values. The virtual-reward plot requires even more context: it is a population-rescaled selection signal whose value depends on the current distance, reward, and visit distributions.