Mock mode. No model calls are made: any upload maps to the trig sample and games come from recorded fixtures. See FIRST_RUN.md step 3 to go live.

Teaching-mechanic library

Every card is a concept-specific configuration of one mechanic family. Cards are data; families are engine code. A card is playable as soon as its family·mode is implemented.

Cards
316
Playable now
303
Flagships
13
Families
14
Modes
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33 cards

Chrono-Bridge

playable

chrono_bridge · general · sequencer.linear

Concept: Any process, timeline, or procedure

Player does: Place the steps in the right order; decoys don't belong

Breaks: The order of steps doesn't matter

A procedure works only because each step prepares the next; reordering breaks the chain.

Cycle Wheel

playable

cycle_wheel · general · sequencer.cycle

Concept: Any cyclic process

Player does: A loop of rooms rotates one stage per clear; trigger the stages in order

Breaks: A cycle has a fixed start and end

A cycle has no first stage; what matters is which stage feeds which.

Proof Ladder

playable

proof_ladder · math · sequencer.linear

Concept: Two-column proofs

Player does: Order the rungs of a proof; one decoy reason doesn't follow

Breaks: If it looks true in the diagram, it's proven

A geometric proof needs a chain of justified statements, since a diagram can look true without the relationship being proven.

Trig Solve Bridge

playable

trig_solve_bridge · math · sequencer.linear

Concept: Solving sin x = k

Player does: Lay the planks: isolate, reference angle, quadrants, all solutions

Breaks: sin x = ½ has one solution

Solving a trig equation means isolating, finding the reference angle, then using every quadrant where the sign matches.

Spread Field

playable

spread_field · math · sequencer.rank

Concept: Standard deviation

Player does: Rank datasets with the same mean by spread

Breaks: Same mean, same data

Two datasets can share the same mean while differing greatly in standard deviation, which measures the spread around it.

Periodic Landscape

playable

periodic_landscape · chemistry · sequencer.rank

Concept: Periodic trends

Player does: Rank elements by atomic radius or electronegativity

Breaks: Atoms get bigger left to right

Atomic radius shrinks left to right across a period as nuclear charge pulls electrons in tighter.

Escape Energy

playable

escape_energy · chemistry · sequencer.rank

Concept: Intermolecular forces

Player does: Rank substances by boiling point from their attractions

Breaks: Boiling breaks covalent bonds

Boiling overcomes the intermolecular forces between molecules; the covalent bonds within each molecule stay intact.

Chromosome Logistics

playable

chromosome_logistics · biology · sequencer.linear

Concept: Mitosis

Player does: Duplicate and separate chromosome sets in stage order

Breaks: Chromosomes duplicate during prophase

Chromosomes duplicate during interphase, before mitosis's stages of prophase, metaphase, anaphase, and telophase begin.

Levels Tower

playable

levels_tower · biology · sequencer.linear

Concept: Levels of organization

Player does: Climb cell → tissue → organ → system → organism

Breaks: Organs are built directly from cells

Cells form tissues, tissues form organs, so organs are built from tissues, not directly from cells.

Krebs Wheel

playable

krebs_wheel · biology · sequencer.cycle

Concept: Krebs cycle

Player does: Rotate the wheel so each intermediate feeds the next

Breaks: Glucose enters the Krebs cycle directly

Glucose is broken down to pyruvate and then acetyl-CoA before entering the Krebs cycle, not directly.

Heart Run

playable

heart_run · biology · sequencer.linear

Concept: Blood flow

Player does: Sprint through the chambers in blood-flow order; valves are one-way gates

Breaks: All arteries carry oxygen-rich blood

The pulmonary artery carries deoxygenated blood to the lungs, so arteries are not defined by carrying oxygen-rich blood.

Rock Cycle Wheel

playable

rock_cycle_wheel · earth_space · sequencer.cycle

Concept: Rock cycle

Player does: Rotate processes so each rock type becomes the next

Breaks: Rocks only change in one direction

The rock cycle has no fixed starting point; igneous, sedimentary, and metamorphic rock can each transform into any other type.

Strata X-Ray

playable

strata_xray · earth_space · sequencer.rank

Concept: Relative dating

Player does: X-ray the cliff; order layers oldest to youngest

Breaks: Layer order says nothing about age

The law of superposition means undisturbed rock layers get younger from bottom to top.

Water Cycle Wheel

playable

water_cycle_wheel · earth_space · sequencer.cycle

Concept: Water cycle

Player does: Restart the cycle by triggering stages in order

Breaks: Clouds are water vapor

Clouds are condensed liquid droplets or ice, while water vapor itself is invisible gas.

Star Life

playable

star_life · earth_space · sequencer.linear

Concept: Stellar evolution

Player does: Route the star through its life stages by mass

Breaks: All stars end as black holes

A star's mass decides its fate: only very massive stars can collapse into a black hole; smaller stars end as white dwarfs or neutron stars.

Tower Access

playable

tower_access · cs · sequencer.linear

Concept: Stacks

Player does: Predict the pop order after pushes and pops

Breaks: First in, first out

A stack is last in, first out: the most recently pushed item is the one that pops first.

Processing Line

playable

processing_line · cs · sequencer.linear

Concept: Queues

Player does: Predict the service order at the processing line

Breaks: The newest arrival is served first

A queue is first in, first out, so the earliest arrival is served before newer ones.

Branch Explorer

playable

branch_explorer · cs · sequencer.linear

Concept: Tree traversal

Player does: Order the rooms visited in pre-, in-, or post-order

Breaks: In-order means top to bottom

In-order traversal visits left subtree, node, then right subtree, which is not the same as visiting top to bottom.

Network Explorer

playable

network_explorer · cs · sequencer.linear

Concept: BFS vs DFS

Player does: Predict the visit order as BFS spreads and DFS dives

Breaks: BFS and DFS visit in the same order

BFS explores level by level with a queue while DFS dives deep with a stack, so they visit nodes in different orders.

Big O Race

playable

big_o_race · cs · sequencer.rank

Concept: Complexity

Player does: Rank runners by growth rate as n explodes

Breaks: An O(n²) algorithm is always slower

Big-O describes growth as input size gets large; an O(n²) algorithm can still be faster than a worse-growth one on small inputs.

OSI Elevator

playable

osi_elevator · cs · sequencer.linear

Concept: Network layers

Player does: Ride a packet down and up the protocol stack

Breaks: Layers can be skipped

Each OSI layer depends on the one below it, so data must pass through every layer in order, never skipping one.

Datapath Relay

playable

datapath_relay · engineering · sequencer.linear

Concept: Instruction execution

Player does: Route an instruction through fetch, decode, execute, memory, write-back

Breaks: The PC changes only on jumps and branches

The program counter advances after every instruction, not only on a jump or branch.

Memory Distance

playable

memory_distance · engineering · sequencer.rank

Concept: Memory hierarchy

Player does: Rank storage by latency and capacity

Breaks: Bigger memory is faster

Memory hierarchy trades capacity for speed: the fastest tiers, like cache, are the smallest.

Reflex Arc

playable

reflex_arc · health · sequencer.linear

Concept: Reflex arc

Player does: Order receptor, sensory neuron, spinal cord, motor neuron, effector

Breaks: Reflexes go through the brain first

A reflex arc routes through the spinal cord, which is what makes it faster than a decision made by the brain.

Timeline Reconstruction

playable

timeline_reconstruction · history · sequencer.timeline

Concept: Chronology

Player does: Rebuild the events in order; dates reveal after placing

Breaks: Events happened in the order the textbook mentions them

A textbook's narrative order can differ from the true chronology of events, which is what dated evidence establishes.

Bill to Law

playable

bill_to_law · civics · sequencer.linear

Concept: Legislative process

Player does: Move the bill through every stage to become law

Breaks: A bill becomes law after one vote

A bill must pass committee, both chambers, and the president's signature or an override before it becomes law.

Business Cycle Wheel

playable

business_cycle_wheel · economics · sequencer.cycle

Concept: Business cycle

Player does: Turn the wheel through expansion, peak, contraction, trough

Breaks: Recessions come out of nowhere

Recessions follow the business cycle's contraction phase, which typically follows a peak of overextended growth.

Memory Stages

playable

memory_stages · psychology · sequencer.linear

Concept: Memory model

Player does: Route information from sensory to short-term to long-term memory

Breaks: Memory records like a video camera

Memory is reconstructed through encoding, storage, and retrieval stages, not recorded and replayed like video.

Plot Arc

playable

plot_arc · literature · sequencer.linear

Concept: Plot structure

Player does: Place scenes along exposition → rising action → climax → resolution

Breaks: The climax is the ending

The climax is the turning point of highest tension, and the resolution afterward is what closes the story.

Paragraph Builder

playable

paragraph_builder · writing · sequencer.linear

Concept: Paragraph structure

Player does: Order claim, evidence, analysis, transition

Breaks: Evidence speaks for itself

Evidence needs analysis connecting it back to the claim; it rarely makes its point on its own.

Word Order Bridge

playable

word_order_bridge · language · sequencer.linear

Concept: Syntax

Player does: Lay word planks in grammatical order

Breaks: Adjectives always come before nouns

Word order rules, including adjective placement, are set by each language's grammar and vary across languages.

Fifths Wheel

playable

fifths_wheel · music · sequencer.cycle

Concept: Circle of fifths

Player does: Rotate the wheel so each key is a fifth from the last

Breaks: Keys are ordered alphabetically

The circle of fifths orders keys by a perfect fifth between neighbors, not by alphabetical letter name.

Gallery Timeline

playable

gallery_timeline · art · sequencer.timeline

Concept: Art chronology

Player does: Hang works in chronological order

Breaks: Styles replace each other cleanly

Art movements overlap in time and influence each other rather than cleanly replacing one another.

Family × genre adapters

Which socket each family mounts on in each genre (LIBRARY §5). The boss socket is always allowed. Hosts built tonight: dungeon, mystery, platformer.

FamilyDungeon crawler
boss: boss
Investigation adventure
boss: accusation
Side-view obstacle course
boss: boss
Grid puzzle / escape room
boss: boss
Management sim
boss: crisis
Truth Finder
chest / boss
Treasure chests; the one bearing the false claim is a mimic
cross_exam / accusation
One witness's claim contradicts the facts; object to the lie
gate / boss
Three doors; the one with the false claim collapses
tile_board / boss
Remove the odd tile to release the chain
event_card / crisis
Advisors' claims; the false one tanks a stat
Sequencer
door / boss
Glyph door pressed in process order
corkboard / accusation
Rebuild the timeline on the corkboard
gap / boss
Bridge planks in order; the wrong order leaves a gap
conveyor / boss
Order the parcels on the conveyor
research_node / crisis
Tech tree order
Tuner
door / boss
Vault rings, catapult, or alchemy dials spinning on the function
lab / accusation
Calibrate the instrument; set the lighthouse sweep
moving_platform / gate / boss
Saw wheels, launch pads, a balloon that only lifts when tuned
lock / beam_board / boss
Dial locks and gear trains
policy_dial / production_line / crisis
Machine settings on the production line
Mapper
altar / enemy / boss
Rune line on the altar floor, or an archery range on a number line
conversation / accusation
At the auction, bid the right magnitude; pin the map
gap / boss
The floor is a number line; land on the value
tile_board / boss
Place the tile at its position on the axis
market / crisis
Place goods on the price line
Sorter
enemy / boss
Type-matched weapons; category-keyed doors
evidence / accusation
File claims into case folders
gate / boss
Only matching-category platforms are solid
goal_pad / boss
Push crates onto category pads
market / crisis
Route goods to districts
Linker
enemy / boss
Chain lightning between pairs
corkboard / accusation
String the board
pickup / boss
Grapple anchors
pipe_board / boss
Flow-style pairing
research_node / crisis
Supply links
Investigator
door / boss
Rooms are hypotheses; clues seal their doors
accusation / corkboard
Pin clues, eliminate suspects, accuse
gate / boss
Clues seal the doors of eliminated hypotheses
tile_board / boss
Logic grid
event_card / crisis
Policy debate with evidence
Function World
altar / boss
Rune track whose floor height is f(x)
lab / accusation
Sensor readings converging on a timestamp
gap / boss
The terrain is y = f(x); the missing tile
tile_board / boss
Track tiles that follow f
market / crisis
Price curve over time
Balance
altar / boss
Alchemy scale; spilled atoms become slimes
archive / accusation
The ledger is off by one entry
switch / boss
Seesaw bridge
lock / boss
Cancel terms, DragonBox-style
ledger / crisis
Balance budgets and flows
Simulator
enemy / boss
Ecology rooms, reactor waves
lab / accusation
Keep the patient stable overnight
moving_platform / boss
Population or glucose lifts
beam_board / boss
Place species so all are fed
crisis / policy_dial
Run the economy or ecosystem
Builder
forge / boss
Craft a molecule, circuit, or golem program
lab / accusation
Build the compound or circuit
switch / boss
Wire the elevator; word-block bridge
tile_board / boss
Valence grid, Lightbot
production_line / crisis
Lay out the factory
Transformer
forge / boss
Crafting-bench machines
lab / accusation
Decode the letter or cipher
pickup / gate / boss
Power-up machine, cipher platforms
conveyor / pipe_board / boss
Route through machines
production_line / crisis
Processing chain
Accumulator
forge / boss
Fill the reservoir to forge the key
archive / accusation
Rebuild totals from rate logs
gap / boss
Fill the pit; velocity ghost
conveyor / boss
Fill tanks
production_line / crisis
Output over time
Recall
enemy / boss
Spells are flashcards, cooldowns are spacing
conversation / accusation
Riddle-keeper interrogation
pickup / boss
Type the term to double-jump
tile_board / boss
Timed word tiles
research_node / crisis
Quick recall boosts research