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FlashBoss

spaced-repetition with boss fights

Build a real vocabulary: English, Latin, French, Swahili, German, Italian, Spanish, Esperanto, or Toki Pona — then prove it in a duel.

Listen · read · repeat · rate · fight

The FlashBoss approach

The target vocabulary is grouped into thematic clusters with progressively longer, and more complex example sentences and explanatory notes. Each cluster ends in a boss fight.

Before you can defeat the boss, you must answer to the words you found most challenging. Win, and those cards graduate.

The cards themselves

Cascading display

Target word — presented with visual cues to aid retention. Current review intervals are shown in stars.

Example sentence — about 90% built from language already learned.

Example translation — an idiomatic rendering of the sentence.

Translation — rate the word, view your notes, 7 to check the rating options.

Notes — grammar, etymology, related language and examples. Press 8 to view notes. They are optional.

A FlashBoss flashcard for the German word die Ehefrau (wife): a colour-coded target word with mastery stars, an example sentence and its translation, the plain translation, and notes.
The Bossfight

How we test

One step forward with a correct answer.

Two steps back with each mistake.

Your easiest cards on positions 1 & 2.

Your most difficult on positions 3 & 4.

Try the live demo →

Three FlashBoss boss fights in a row, each announced by its own title card. LatAm Spanish asks for the Spanish word for heart, Latin Roots asks which word means a glass tank for fish, and The Guide asks you to name the spell from its rules text. Each fight reaches the killstroke position, loses it to a wrong answer and is pushed two steps back, then climbs again and wins. try the demo

Five packs ship free

Add additional decks as you go.

Free in the base game

English Advance & Adept
German Core
Esperanto Core
Toki Pona

The Roots Series

German, Norman, Latin and Greek Roots — the history English is built from, and four of the six steps on the immersion path.

Full language courses

Learn Latin, French, Swahili, German, Italian, Spanish or Esperanto with FlashBoss. Most run 3,000 words across Core, Pareto 1 and Pareto 2 — Latin is a 2,000-word reading course, and Swahili's Core is out with its Pareto packs to come.

Not a language at all

The Guide — the rules a game master needs in their head, as flashcards. 1,205 cards in 62 clusters, 5E compatible.

Scientia est Potentia.Knowledge is power