LTX Attn Block Override

Yes, the class name is misspelled - "Attentio," no second N. Don't let that throw you; it's a real node and it does a small, specific job in LTX's video-editing toolkit. Think of it as a block picker. When you're doing FlowEdit-style editing on an LTX video and you want to preserve structure by injecting the source's attention into the edit pass, you rarely want to do that on every transformer block. This node is how you say "these blocks, not those."

That matters because attention injection is a blunt instrument. Inject on all blocks and the edit clings so hard to the source that your new prompt barely lands. Inject on none and you lose the composition you were trying to keep. The sweet spot is a subset - and which subset changes the character of the edit - so you need a clean way to specify it. That's this.

How it works

You type a list of block identifiers into one text field, and the node hands back an LTX_BLOCKS object: a typed bundle that downstream injection nodes understand. On its own it does nothing to your image or latent - it's a selector, a piece of config you route into the node that actually performs the injection (LTXPrepareAttnInjections has a blocks input built exactly for this). Nothing gets computed here; you're just naming targets.

The inputs and outputs that matter

There's exactly one input:

• blocks (multiline STRING) - the list of transformer blocks to override. You write them in here as text. Which blocks to name is the whole game, and honestly it's trial and error: start narrow, widen if the edit isn't holding structure, narrow again if it's ignoring your prompt.

And one output:

• LTX_BLOCKS - wire it into the blocks input on LTXPrepareAttnInjections (or whichever injection node your workflow uses).

That's the entire node. It's plumbing, and it's fine that it's plumbing - the alternative is hardcoding block lists inside another node's settings, which is worse.

How to install it

ComfyUI Manager: Ctrl+M, Install Custom Nodes, search LTXVideo, install, restart. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/Lightricks/ComfyUI-LTXVideo

then restart. It ships in Lightricks' official LTXVideo pack. This node itself pulls no models - but the editing workflow it belongs to runs on the LTX checkpoints, so expect the pack's usual footprint (a 22B-class LTX model, the Gemma 3 text encoder, real VRAM) elsewhere in the graph.

Common issues & troubleshooting

You searched "LTXAttentionOverride" and found nothing. Spelling. The node's registered class is LTXAttentioOverride. Search the node menu for "LTX Attn Block Override" - its display name - or just browse the ltxtricks category.

Your block list did nothing. This node is inert unless its LTX_BLOCKS output is actually connected to an injection node and that injection is switched on (query/key/value flags set, inject steps > 0). If the downstream node isn't injecting, naming blocks changes nothing.

You're not sure what to put in the field. Copy the format from a working FlowEdit example workflow in the pack rather than guessing syntax. This is an advanced editing node - it assumes you already have the injection pipeline built and are tuning it, not standing it up cold. If you don't have that pipeline yet, that's the thing to build first; this node is the last 5% of it.