
FlashBoss
Build vocabulary with spaced repetition and boss fights. Listen · Read · Repeat · Rate · Fight. Choose your master: from 5 minutes to half an hour plus per day. Four starter packs free; full 3,000-word courses in four languages, from total beginner to C1 language in use.
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13 itemsAbout the Game
FlashBoss: Spaced Repetition and Boss Fights
Listen · Read · Repeat · Rate · Fight. A vocabulary course built around spaced repetition and boss fights. Foreign-language courses cover 3,000 of the most useful words, with naturally structured example sentences, English translations, and high-quality text-to-speech audio on every card. English packs teach with a definition and two example sentences per card.
Each DLC contains 1,000 new vocabulary words, with many more related words taught in the notes field.
How it works
Each card sets a target word in example sentences at a level you can follow. Words come in thematic clusters, and every cluster is gated by a boss fight: win it and the cluster graduates — your deck gets smaller as you go.
Try before you buy
Full word lists for every pack, every reference lesson, and a playable boss-fight demo are free to browse on the website. Link in the right sidebar.
Two ways to play
Work the structured course at your master's pace — or skip the syllabus and just fight. Every tier you clear becomes a low-stakes boss rush, for unlimited review.
Bank days off
Once the day's work is done, you can use a magic spell to bring tomorrow's workload forward — but be careful.
Boss fights
Each cluster ends in a duel: one step forward for a correct answer, two steps back for a mistake. As you practice, your flashcards are ranked by difficulty. The first two spaces deal you your easiest cards, and the last two, the hardest. This means you cannot defeat a cluster without facing your biggest challenges.
Choose your master
Six masters set six daily paces — from Luna's 8 cards a day to Aquila's 34. Choose by temperament and time commitment.
Some masters are bossy: they cap boss fights at three per day to protect you from burnout. Others are advisory: they'll warn you it's a bad idea, then let you do what you want.
The packs
Four starter packs ship free:
English Advance — the practical English of adult life: forms, letters, the fine print. 500 words.
English Adept — sharper English for how you think, write, and speak. 1,000 words.
German Core — the first 1,000 words of German, including a cultural integration section.
Esperanto Core — one of the easiest languages to learn; 1,000 words goes far.
Further FlashBoss content:
Latin Roots — build English vocabulary by recognizing the parts that make the whole. 1,000 words over 500 cards.
German Roots — the Germanic backbone of everyday English.
Norman Roots — the French that arrived in 1066 and stayed.
Greek Roots — the vocabulary of science and medicine. (in development)
Full 3,000-word courses in German, Spanish, Italian, and Esperanto. A1–C1 content arc.
All English content in FlashBoss is American English.