Seedance Reference to Video (Symbiotica)

Seedance is ByteDance's closed video model - reference images, clips and audio become a video - and it has no open weights, so the only door into it is an API. Symbiotica Seedance Reference is this pack's door: it runs Seedance 2.5, 2.0, 2.0 Fast or 2.0 Mini from inside a ComfyUI graph, and it's deliberately not the ComfyUI official node. The pitch in the README is billing: it routes through Cloudflare AI Gateway rather than to a ComfyUI account, so a studio's spend stays on its own BYOK key and shows up in its own analytics.

If you're a hobbyist this node is aimed past you. The community's stance on API video is well documented - per-call cost, your data leaving the machine, and a filter you can't remove. Seedance specifically is the model the KB quotes people rejecting as "extremely expensive" and "not local, through an api? Nvm then." None of that is wrong; it's the price of using a model you were never allowed to download.

How it works - two routes, and it prefers the better one

The node has two arms. Where the studio gateway is configured (SYMBIOTICA_AIG_BASE, SYMBIOTICA_AIG_TOKEN, ORDER_STUDIO), calls go through AI Gateway's fal passthrough - the studio's own stored key pays, selected by alias, and this is the route the node is built for. Renders take minutes, so it submits to fal's queue and polls rather than holding a connection open; cancel stops the wait.

Where only Cloudflare's model catalog is configured, it falls back to it - and the README is blunt that this is a poorer route: a shared key pays, reference clips can't ride at all, and the 2.0 family is cut to four images with no audio. The sockets don't change - a graph is shared between boxes - so what the fallback can't carry is refused by name at render time rather than hidden.

The models differ, and the node only exposes what each one can carry: 2.5 takes thirty reference images, ten clips and ten audio tracks and runs to 30s; the 2.0 family takes nine images, three clips, three audio and stops at 15s. 2.0 reaches 4k, 2.5 reaches 1080p, Fast and Mini stop at 720p. References are resampled to 2048px JPEG before sending, and the whole set is refused above 8 MB - the gateway stores no log above 10 MB, and a call with no log is spend that never reaches the cockpit. A few seconds of 720p footage eats most of that budget, which is why the clip slots are more than the ceiling lets you fill.

The inputs

• model - the Seedance version (a dynamic combo, so the widgets below it adjust to the chosen model). 2.5 is newest and longest; 2.0 reaches 4k; Fast trades quality for speed; Mini is the cheap lever.
• seed - decides whether this node re-runs. Results are not reproducible from it - Seedance doesn't offer that - so treat it as a re-run trigger, not a reproducibility knob.
• watermark - ByteDance's watermark. Offered for parity with ComfyUI's node, but the fal route has no such parameter, so asked for there it's refused rather than dropped - the same graph never renders watermarked on one box and clean on another.

The output

• video - one VIDEO. Wire it into a video preview, a save, or the pack's composition nodes.

Install and keys

Standard pack install - search Symbiotica in ComfyUI Manager, or:

cd ComfyUI/custom_nodes
git clone https://github.com/symbiotica-ai/comfyui-nodes.git symbiotica
pip install -r symbiotica/requirements.txt

Restart after. Keys: the gateway route needs the three SYMBIOTICA_AIG_*/ORDER_STUDIO variables (or the Settings → Symbiotica → AI Gateway fields on Comfy Desktop); the direct fal arm takes FAL_KEY or FAL_API_KEY. The direct arm is the only one that can't be billed to a studio.

Gotchas

Cost is the first one: a 10-second 1080p Seedance clip is priced per render, and the KB's own framing is that video jobs are where an API session gets expensive fast. The 8 MB reference ceiling is the second - a couple of reference clips can exceed it, and the node refuses the whole set rather than trimming. That's intentional (silent trimming is how renders ship wrong), but plan your clip budget. And the watermark asymmetry is a genuine trap if you've been using ComfyUI's own node: a graph that renders clean on one box can be refused on another for asking for a watermark the route can't carry.