Skimmed CFG - replace

The replace node is the bluntest instrument in the Skimmed_CFG pack, and for some workflows that's a feature. It takes a model, patches it, and does exactly one thing: at every latent position where the positive and negative predictions conflict, it copies the positive's values over the negative's. The author's description: it nullifies - gives an effective scale of 1 to - the effect of the values the filter targets.

Think about what that does to CFG. CFG works by extrapolating away from the unconditioned (negative) prediction. Where the negative has been replaced by the positive, there's nothing to push against, so guidance at those positions just stops. Net result: you keep the full prompt adherence everywhere the model agrees with itself, and the "burn" positions - where the two predictions were yanking in opposite directions and the extrapolation was about to overshoot - get zero pressure. No scales to tune, no percentages, no flip.

Using it

Wire it model loader → SkimReplacePreCFG → KSampler. MODEL in, patched MODEL out. The whole interface is the decision to have it on the wire. Since it's a model patch, A/B it against the same seed with and without.

It's a good match for a strong, specific negative - the author's own advice is that a good negative is a style negative. Replace keeps the useful steering and discards the part of the negative that's smearing the composition.

Install

Part of Extraltodeus/Skimmed_CFG - one Python file, zero pip dependencies, no model downloads. ComfyUI Manager: search "Skimmed_CFG" (Extraltodeus), install, restart. Or:

cd ComfyUI/custom_nodes
git clone https://github.com/Extraltodeus/Skimmed_CFG

Restart after either.

Caveats

• Inert at CFG 1. No unconditioned pass means nothing to replace; this is an SD 1.5/SDXL-lineage tool for when you're running the sampler CFG high.
• Hard-replacing can flatten texture at the targeted positions more than the linear-interpolation variant. If your results look "skinned," swap in SkimmedCFG_LinInterp_CFG_PreCFG and let it blend instead.
• Current name for what used to be "Skimmed CFG - replace"; old workflows referencing that name can flag missing after the January 2026 rename - this node is the drop-in.

When the answer to "my negative keeps fighting my positive" is "fine, the negative loses," this is the node that says it with one wire.