Make a retro monster-battle game intro with Claude Opus 5.5 (with music and sound effects)

Make a **retro monster-battle game intro with sound** — the kind of opening movie early-2000s handheld RPGs played before the title screen: two creatures face off, clash, and the title slams in.

**The two fighters**
- use the two fighters I describe below. If I left one blank, invent an original creature that contrasts with the other in color, shape and element
- original designs only: do not copy any existing game's characters, logos, title lettering or music. Borrow the era's look, not a specific game
- before building, describe each fighter in three short lines: silhouette, colors (hex), signature move

**Plan first — show me this before the code**
- a beat table: start–end time, what is on screen, what sound plays. Times add up to the total
- follow this arc: (1) a quiet opening — a star field or sparkles, a low rumble; (2) quick flashes of each fighter in silhouette, then a close-up reveal of its eyes; (3) the standoff — the camera cuts between the two, faster and faster; (4) the clash — both lunge, the screen flashes white on impact, then two or three exchanges using their signature moves; (5) the title slams in, a shine sweeps across the letters, and "PRESS START" blinks
- the last beat holds: the title stays and "PRESS START" keeps blinking for at least 2 seconds

**Look — handheld console era**
- pixel art: draw on a small canvas (240×160 for horizontal, 144×256 for vertical) and scale it up by a whole number with no smoothing, letterboxed to fit any browser window. Horizontal if I did not say
- at most 32 colors, listed in the plan. Hard pixel edges: no blur, no soft gradients, no anti-aliasing
- motion the way those games did it: sprite frames (2–4 per action), screen shake, speed lines, palette flashes, and background layers scrolling at different speeds
- each fighter is at least 48 pixels tall with its own idle breathing frames; it stays recognizable in every frame and never stretches, tears or passes through the other fighter
- title text in pixel lettering you draw yourself, in the language of my title

**Sound — made in code**
- chiptune through the Web Audio API only: two square-wave voices, one triangle bass and one noise channel, like a handheld sound chip. An original melody, with the tempo (BPM) stated in the plan
- sound effects land exactly on the picture: a whoosh on every dash, a noise burst on every hit, a rising sweep before the title, a chime on the shine
- browsers block sound until a tap: open on a simple "Tap to start" screen; the picture and the music start together from 0 on the tap, both driven by the same clock so they never drift

**Build — it must work for someone who does not code**
- one self-contained HTML file, no external images, fonts or audio files; draw and synthesize everything in code. All motion is driven by one `render(t)` function of time in seconds (only seeded randomness)
- always print the whole HTML in one code block in your answer, even if you also saved a file — I may only see your answer. Never say you saved, ran or checked a file you did not
- 30 fps
- a **"Save video" button** in a corner, labeled in my language. Pressing it replays from 0 and records exactly one full run of the stage **with the sound** (the canvas stream plus the audio stream) using MediaRecorder, then downloads it. Prefer MP4 when `MediaRecorder.isTypeSupported` allows it, otherwise WebM. Show a progress bar while recording, and never include the button in the recording
- before handing over, walk through every beat boundary and fix sprites leaving the frame, text overlapping sprites, and sound effects that fire off the hit
- after the file, give me three short steps in plain words: how to open it, how to turn the sound on, and how to save the video