A browser-based trainer for tracking enemy Flash (and any 5-minute cooldown) in League of Legends. Simulates the LoL chat so you can drill the muscle memory of logging timers quickly under distraction.

Play it: https://gronuj.github.io/flashtimer/

1. Start a session — pick clock speed, flash frequency, length (3 / 5 / 10 min or unlimited), and optional modes.
2. Enemy flashes pop up as chat messages (e.g. 14:20 Jgl (Jgl): Mid used Flash).
3. Press Enter, type the return time as role + MMSS (flash time + 5:00), press Enter again. Example: a Mid Flash at 14:20 → type mid1920. ADC accepts adc/ad, jungle accepts jgl/jg. The logging window depends on Flash Frequency: 5s (insane) / 10s (high) / 15s (medium) / 20s (low).
4. Catch it in time to score; build a streak for multipliers and climb the rank badge (Iron → Challenger). Misses cost a small amount (-50 score, -1 streak, -1 bubble stack) but no longer wipe progress.
5. Session ends with a results screen; your score per session is charted in Stats.

Between flashes, gold bubbles pop up at random screen positions for ~1.2s. Click them to:

• gain +25 score and +1 stack to the bubble bank (uncapped — high stacks are the goal),
• each stack adds +0.2x multiplier on top of the streak multiplier (multiplicative), e.g. streak 5 with 10 banked bubbles = 2.0x × 3.0x = 6.0x on the next catch,
• click pitch climbs slowly with stack count so you can hear depth grow.

The bubble game pauses and clears all on-screen bubbles the moment any flash is active — flashes always take priority. Stacks erode one at a time on misses, so banking bubbles is a long-term investment that risks evaporation if you sleep on a timer.

• Clock speed (1x / 2x / 5x / 10x) — how fast the game clock advances, independent of the catch window. Past 45:00 the clock soft-resets to a fresh early-game window once outstanding flashes are resolved (since flash + 5:00 wraps past the 4-digit input format).
• Flash frequency (insane / high / medium / low) — how often events spawn, and how long you have to log each one (5 / 10 / 15 / 20 real-time seconds).
• Hidden timers (hardcore) — chat hides the exact time the Flash went out; you calculate it.
• Simultaneous spells (teamfights) — occasional double flashes.
• Fake chat distractions — teammate spam to filter out while you track.
• Sound cues — short WebAudio blips for flash spawns, catches (pitch rises with streak), misses, and bubble pops (pitch rises with bank). No audio assets, fully synthesized.

Requires Python ≥ 3.13 and uv.

uv run uvicorn main:app --reload

Then open http://127.0.0.1:8000/.

The backend is only a thin FastAPI shim that serves the static/ directory; all game logic lives in static/script.js.

• Vanilla JS / HTML / CSS — no framework, no build step.
• FastAPI (local dev only).
• Inline SVG for branding and charts.
• localStorage for stats persistence.

Not affiliated with Riot Games. FlashTimer is a fan-made practice tool.