EA Motion Bias (Lightning)

Wan 2.2 is a two-pass beast: a high-noise model handles motion and composition, a low-noise model refines detail, and if you're running it with Lightning LoRAs you have to coordinate steps, sigma schedules, and per-stage LoRA weights across two samplers. The math nodes for that get ugly fast - and every preset thread in r/comfyui is someone begging for a workflow that handles the split for them. EA Motion Bias (Lightning) is a calculator node that collapses all of that coordination into one dropdown and a motion-bias dial.

It doesn't sample anything. It computes the values - steps, the split point, a sigma list, and the two Lightning weights - that you then feed into your high/low KSamplers. It's the "settings" half of the two-stage workflow, packaged as a single node.

The presets

The preset dropdown encodes the author's tuned profiles, and they're exact - the source ships hard-coded sigma lists for each:

• Lightning Default 2/2 - 4 steps, split at 2, both weights 1.0, no extra noise. This matches the stock Wan 2.2 Lightning workflow (Euler, CFG 1/1).
• Aggressive 3/2 (the default) - 5 steps, 3 high / 2 low, high weight 1.25, low 1.0, with add_noise_high on. More motion, at the cost of some stability.
• Balanced 3/2 - the safer middle ground, slightly lower high weight.
• Speedrun 4/1 - 4 high steps, 1 low: fastest, best for quick iteration.
• Detail 6/2 - 6 steps for quality over speed.

Pick one and the outputs are what you need for the two-stage graph: steps, split_step (the high/low boundary), sigmas_str (a comma-separated sigma list for the sampler's sigmas input), lightning_high_weight, lightning_low_weight, and add_noise_high / add_noise_low boolean hints for the sampler's add_noise inputs.

The custom path

Set preset to Custom and the real knobs appear: motion_bias (0–1) is the dial - push it up and the split shifts later (more high-noise steps), the high weight rises, and the low weight eases off, which is the "more motion" trade. profile picks the sigma curve shape: big_drop (the default) drops quickly then lingers, while hold_high keeps the early sigmas near 1.0 longer. base_high / base_low are the anchor weights the bias scales from. min_low_steps keeps the low stage from getting starved when you crank the bias.

The honest caveats

This node works best with native KSampler two-stage setups, not the triple-stage base+high+low workflows some folks use - those need a different kind of orchestration (the well-regarded TripleKSampler node handles that). Also: the outputs are numbers, but you still have to set the sampler and scheduler yourself - the node's UI overlay literally highlights those fields to remind you. And CFG: Lightning is distilled, so it wants CFG ~1, not 7. The preset table carries CFG values internally but doesn't export them as wires, so set them manually per the preset you chose.

It's a helper, not a magic box - but for anyone wrangling Wan 2.2 Lightning by hand, it replaces a clump of math nodes with one node and a dial.

Install

Part of comfyui-ea-nodes: Manager → search comfyui-ea-nodes, or git clone https://github.com/ExoticArts/comfyui-ea-nodes into custom_nodes/, restart, hard-refresh. No extra dependencies.