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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Filter

22 cards

Unit Pipeline

playable

unit_pipeline · math · transformer.composition

Concept: Dimensional analysis

Player does: Chain conversion-factor pipes; joints connect only when units cancel

Breaks: Units are labels you can drop

Units multiply and cancel like numbers, which is exactly how a chain of conversions works.

Order of Operations Forge

playable

order_of_ops_forge · math · transformer.trace

Concept: Order of operations

Player does: Predict what the calculator machine outputs for a nested expression

Breaks: Operations always go left to right

Operations follow precedence and grouping, not reading order.

Function Factory

playable

function_factory · math · transformer.function_machine

Concept: What a function is

Player does: Feed inputs, watch outputs, predict the output for a new input

Breaks: A function must be a formula

A function is any rule pairing each input to exactly one output, whether given by a formula, table, or graph.

Machine Pipeline

playable

machine_pipeline · math · transformer.composition

Concept: Composition

Player does: Order two machines so the crate exits as the target

Breaks: f(g(x)) = g(f(x))

Function composition is generally not commutative, so f(g(x)) and g(f(x)) usually differ.

Pattern Path

playable

pattern_path · math · transformer.function_machine

Concept: Arithmetic & geometric sequences

Player does: Jump to the stone holding the next term

Breaks: Every sequence adds a constant

An arithmetic sequence adds a constant difference, but a geometric sequence multiplies by a constant ratio instead.

Derivative Machine

playable

derivative_machine · math · transformer.function_machine

Concept: Differentiation rules

Player does: The machine turns f into f′; predict its output for a new f

Breaks: d/dx x³ = 3x³

The power rule brings the exponent down as a coefficient and reduces it by one, so d/dx x³ = 3x², not 3x³.

Genome Repair

playable

genome_repair · biology · transformer.encode

Concept: DNA base pairing

Player does: Rebuild the damaged strand by complementary pairing

Breaks: A pairs with G

DNA base pairing is fixed: A pairs with T, and G pairs with C.

RNA Assembly

playable

rna_assembly · biology · transformer.encode

Concept: Transcription

Player does: Read the template strand and assemble the mRNA (U for T)

Breaks: mRNA is an exact copy of the template strand

mRNA is complementary to the DNA template strand, not an identical copy, and it swaps thymine for uracil.

★ Protein Factory

playable

protein_factory · biology · transformer.encode

Concept: Translation

Player does: Route codons to amino acids with the codon table to build the chain

Breaks: Each nucleotide codes for one amino acid

A group of three nucleotides, a codon, specifies one amino acid, not a single nucleotide.

Photosynthesis Recipe

playable

photosynthesis_recipe · biology · transformer.composition

Concept: Photosynthesis

Player does: Route light, water, CO₂ through the stations to make glucose

Breaks: Plants get their mass from the soil

Most of a plant's mass comes from carbon dioxide fixed by photosynthesis, not from the soil.

Respiration Forge

playable

respiration_forge · biology · transformer.composition

Concept: Cellular respiration

Player does: Run glucose through glycolysis, Krebs, and the ETC to charge ATP

Breaks: Plants don't do cellular respiration

Plants perform cellular respiration to make ATP just as animals do, in addition to photosynthesis.

State Containers

playable

state_containers · cs · transformer.trace

Concept: Variables & assignment

Player does: Predict each container's value after the instructions run

Breaks: x = x + 1 is an impossible equation

In code, = is assignment, not algebraic equality, so x = x + 1 replaces x's stored value with one more than itself.

Branch Doors

playable

branch_doors · cs · transformer.trace

Concept: Conditionals

Player does: Predict which door the branching world opens for the current state

Breaks: Both branches of an if run

An if statement runs exactly one of its branches, chosen by whether the condition is true or false.

Nested Rooms

playable

nested_rooms · cs · transformer.trace

Concept: Recursion

Player does: Each room holds a smaller copy; predict the result as base cases return

Breaks: Recursion never stops

Recursion terminates once it reaches a base case, which stops the chain of smaller calls from growing further.

Indexed Inventory

playable

indexed_inventory · cs · transformer.trace

Concept: Arrays & indexing

Player does: Fetch items by slot from a zero-indexed inventory

Breaks: Indexes count from 1 in every language

Many languages index arrays starting at 0, so the first element sits at index 0, not 1.

Ordering Conveyor

playable

ordering_conveyor · cs · transformer.trace

Concept: Sorting algorithms

Player does: Predict the conveyor after pass k of bubble or insertion sort

Breaks: Every sort does the same work

Different sorting algorithms compare and move elements in different patterns, so their intermediate states differ.

Bucket Router

playable

bucket_router · cs · transformer.function_machine

Concept: Hashing

Player does: Predict each key's bucket from h(k) = k mod m; spot collisions

Breaks: Hashing sorts the keys

A hash function maps keys to buckets for fast lookup; it does not order the keys.

Memory Warehouse

playable

memory_warehouse · cs · transformer.trace

Concept: Caching & locality

Player does: Predict hits and misses as requests arrive

Breaks: Every memory access costs the same

A cache hit is far cheaper than a miss, so locality of access strongly affects real performance.

Cipher Door

playable

cipher_door · cs · transformer.encode

Concept: Binary, hex, encodings

Player does: Translate the carving from binary or hex to unlock the door

Breaks: Hex digits only go 0–9

Hexadecimal digits run 0 through F, using A–F to represent values ten through fifteen.

Signal Railway

playable

signal_railway · engineering · transformer.trace

Concept: Multiplexers

Player does: Set select lines so the right input track reaches the output

Breaks: Select lines carry the data

Select lines only choose which data input is routed through; they never carry the data themselves.

One-Bit Room

playable

one_bit_room · engineering · transformer.trace

Concept: Flip-flops

Player does: Predict the stored bit after each clock edge

Breaks: Outputs change whenever inputs change

A flip-flop's stored output changes only at a clock edge, not whenever its inputs change.

Conjugation Forge

playable

conjugation_forge · language · transformer.function_machine

Concept: Verb conjugation

Player does: Feed person + tense; predict the machine's verb form

Breaks: Irregular verbs follow the regular pattern

Irregular verbs conjugate by their own memorized pattern instead of the regular rule.

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