ByteDance Seedance 2.0 Fast First Last Frame (Channel Edition)

Seedance 2.0 comes in two speeds, and "Fast" is exactly what it sounds like: same first-last-frame generation trick, faster turnaround, cheaper per job - with a modest quality trade. This is the Channel Edition Fast FLF node, the one you reach for when you're iterating on a concept and want five drafts before lunch rather than one polished clip. When the idea's locked, you'd move up to the full Seedance 2.0 FLF node for the final render.

How it works

Same cloud machinery as every BizyAir node: your first-frame image (and optional last frame) upload to api.bizyair.ai, the request hits the seedance-2-0-fast-base/flf-to-video endpoint, and the finished clip downloads back into ComfyUI as a native VIDEO tensor. No local GPU work, no model files. Billed per job against BizyAir credits.

Inputs that matter

• first_frame_url - the required starting image, the anchor of the whole clip.
• last_frame_url - the optional ending frame (one image, up to 30 MB). Include it when the destination matters; omit it to let the model improvise.
• prompt - the motion between the frames. Action verbs beat adjectives here.
• resolution - defaults to 2k; native tiers are 480p/720p/Native1080p, with 1080p/2K/4K as 720p-based upscales.
• duration - seconds, default 6 (range 4–15), a touch shorter than the standard node's default - fitting for a fast draft tier.
• ratio - aspect ratio, default 16:9.
• seed - integer, default 0, for reproducible drafts.
• generate_audio - default on; flip off for silent, cheaper-feeling drafts.
• return_last_frame - default off; on to receive the final frame as an image.
• api_config / skip_error - per-request key/base override and placeholder-on-error.

Outputs: video, request_id, urls.

Install and get going

ComfyUI Manager → "BizyAirPlus", or:

cd /path/to/ComfyUI/custom_nodes
git clone https://github.com/siliconflow/BizyAirPlus.git
cd BizyAirPlus
python -m pip install -r requirements.txt

Restart, register at bizyair.ai, set the key in Settings > BizyAirPlus > API Key (or BIZYAIR_API_KEY), and click the BizyAirPlus action-bar toggle to ON.

Gotchas

Setup: missing key, toggle off, or deps in the wrong Python (python -m pip show bizyair-cloudberry) - the eternal trio. For the Fast tier specifically, set your expectations: it's built for speed, so intricate motion and fine detail degrade first. If a draft's middle section looks warped, that's the speed/quality trade doing its job, not a bug - lock the concept, then re-run on the full Seedance node. And keep the FLF anchors consistent (matching style, lighting, and subject) or the generated middle will visibly fight itself.