Sulphur 2 — Generate AI Video
Free. Open Weights. No GPU Needed.
Fine-tuned on 125,000 real clips. Fixes broken limbs, camera jitter, and prompts base LTX 2.3 ignores.
No GPU? Generate in your browser. Have a GPU? Download the weights and run it locally.
What Is Sulphur 2?
Sulphur 2 is an open-weights AI video model from the SulphurAI community. It's a fine-tune of Lightricks' LTX 2.3 — same 9B parameter architecture, retrained on 125,000 real-world clips with fewer content restrictions.
Released May 2026 by contributor FusionCow. The training dataset was ~500 GB of 10-second, 24fps clips. Filtered to remove illegal content and 2D animation only. Everything else stayed in — to improve realism and cut down on the refusals you get from commercial platforms.
It's architecture-identical to LTX 2.3. Drop it into your existing ComfyUI setup — no node rebuilds, no new extensions.
| File | Purpose | VRAM |
|---|---|---|
| sulphur_dev_bf16 | Full quality — 46 GB | 24–32 GB |
| sulphur_dev_fp8mixed | Balanced — 29 GB | 16 GB |
| sulphur_distil_bf16 | Faster generation | Lower |
| sulphur_lora_rank_768 | LoRA — stack on dev | — |
| 4 ComfyUI JSONs | T2V + I2V workflows | — |
| Qwen 3.5 9B GGUF | Local prompt enhancer | — |
No GPU? Use the Browser.
Have a GPU? Go Local.
Online Generator — No Setup Required
Generate at sulphur2ai.com. No install, no model download, no VRAM needed. Free credits on signup. Runs server-side.
- Up to 1080p MP4 output
- 16:9, 9:16, 1:1 aspect ratios
- No watermarks on any export
- Commercial use on every plan
- Most generations done under 2 minutes
- Queue multiple jobs without waiting
Local / ComfyUI — Full Control
Download the weights from HuggingFace. Swap in the checkpoint. Four official JSON workflows load straight into any existing LTX Video ComfyUI setup.
Hardware minimums
- FP8 Mixed: 16 GB VRAM
- BF16 Dev: 24–32 GB VRAM
- Disk: 100 GB+ for full setup
- Install or update ComfyUI
- Download base LTX 2.3 dependencies
- Download weights from HuggingFace
- Import one of the 4 included workflow JSONs
- Swap the checkpoint node to your chosen weight
Already Running LTX 2.3?
Here's What Changes.
| Dimension | Sulphur 2 | LTX 2.3 Base | Runway Gen-4 | Sora |
|---|---|---|---|---|
| Price | From $0 | Hardware only | $15–$95/mo | $20+/mo |
| Open weights | ✓ | ✓ | ✗ | ✗ |
| Motion quality | Fine-tuned on 125k clips | Base training only | Proprietary | Proprietary |
| Limb deformation | Reduced by fine-tune | Known issue | Proprietary | Proprietary |
| Image-to-video | ✓ | ✓ | ✓ | ✗ |
| Local / offline use | ✓ | ✓ | ✗ | ✗ |
| Official ComfyUI workflows | ✓ 4 JSONs | Community only | ✗ | ✗ |
| Content restrictions | Legal content only | Moderate | Conservative | Conservative |
| Prompt enhancer | ✓ Qwen 3.5 9B | ✗ | Cloud only | Cloud only |
Same base architecture as LTX 2.3. You keep your existing workflow. You just get cleaner output on the other end.
Text-to-Video and Image-to-Video
Both modes fully supported. Fine-tuned to fix the specific motion problems that make base LTX 2.3 frustrating in real production.
Prompt-Driven Cinematic Generation
Type a description. Sulphur 2 renders a temporally stable clip — consistent subject motion, lighting, and camera behavior across every frame. Fine-tuned specifically to eliminate limb deformation and camera jitter.
Animate Any Still with Precision Control
Upload one image as your starting frame. Describe the motion. Sulphur 2 animates it while keeping subject identity, color, and composition intact. Supports dolly, orbit, push-in. First-frame and last-frame anchoring both work.
Qwen 3.5 9B Prompt Enhancer
The bundled Qwen 3.5 9B rewrites your vague description into a structured, cinematically-worded shot brief before it hits the video model. You don't need to learn prompt engineering. Just describe what you want.
Native Multi-Format Support
16:9 for web and YouTube. 9:16 for Reels, TikTok, and Shorts. 1:1 for Instagram feed. Up to 1080p on all formats. 10-second native clip length. Renders natively — no cropping, no letterboxing.
Which Weight Should You Download?
Most common setup question. Here's the short answer based on your GPU.
Full quality tier. Runs cleanly on a 3090, 4090, or better. This is the reference quality — use it for final exports.
Some quality trade-off versus BF16, but most users report it's hard to spot at 720p. Works well on a 4080 or 3090 with limited VRAM headroom.
Smaller file, faster sampling. Good for rapid iteration before a final render. Stack with the dev base for best results.
Use it to modify style, improve motion, or add Sulphur-specific behavior on top of the dev base. Not required to start — download after you've run your first generations.
What Sulphur 2 Actually Produces
Community-generated clips — via ComfyUI locally or through the online generator.
"Luxury ceramic coffee cup on dark slate, steam rising, soft studio backlight, warm rim glow, slow dolly-in, macro lens"
"Filmmaker under neon city lights, rain on pavement, slow push-in, moody blue and magenta, shallow DOF, film grain"
"Mountain lake at sunrise, mist rolling, birds drifting, slow aerial tracking shot, warm golden light, photorealistic"
"Slow orbit camera, light sweeping surface left to right, subtle reflection shift, maintain original composition"
"Natural hair movement in light breeze, golden hour lighting shift, preserve face identity, shallow depth of field"
"Fashion model in modern gallery, smooth handheld camera, white walls, editorial style, vertical social format"
Real Workflows, Real Results
Product & Brand Video
Animate a product photo with a slow orbit, dolly, or light sweep. Subject stays consistent frame to frame. Marketing-quality footage in minutes, not a full shoot day.
Film Pre-Viz & Storyboarding
Turn script scenes into moving previews before you shoot. Dramatic or mature scenes render without the refusals you hit on Runway or Sora.
Social Content at Scale
Native 9:16 for Reels, TikTok, and Shorts. Consistent motion quality across clips. Fast enough for teams producing content every day.
Medical & Scientific Visualization
Anatomical sequences, surgical previews, biological process animations. Sulphur 2 accepts this. Most commercial platforms don't.
Documentary Reconstruction
Render period-accurate environments from written descriptions or reference photos. No refusals on legal historical content.
Concept Art Animation
Upload your artwork. Describe the camera move or atmosphere. Sulphur 2 animates it without changing your original design.
What People Are Saying
Motion quality is noticeably cleaner than base LTX 2.3. Limb movement doesn't break. Camera stays stable. This is what open-source video should feel like.
Dropped the workflow JSON in, loaded the FP8 weights, had my first video in under 20 minutes. Distil LoRA runs clean on my 24 GB card at 720p.
Finally a model that doesn't refuse my storyboard prompts. I'm generating character scenes that Runway rejects outright.
First AI video model where camera motion actually does what I describe. Saves a full day of storyboarding on every client pitch.
I turn a product photo into a polished clip in minutes. Subject consistency across frames genuinely doesn't look AI-generated.
1080p, clean MP4, no watermark — exactly what we needed for paid ad placements. The per-second credit model is predictable once you know your clip length.
Sulphur 2 Pricing — Simple Plans, No Surprises
Credits power Sulphur 2 text-to-video and image-to-video in your browser — up to 1080p MP4, 16:9 / 9:16 / 1:1 formats, no watermarks, commercial usage included. One-time packs with no subscription; credits never expire and are only deducted on successful generation. See the full feature overview before you buy.
Starter
$9.9
100 credits · $0.099/credit
Good for testing T2V and I2V before committing to more.
- T2V + I2V up to 1080p
- 16:9, 9:16, 1:1 formats
- No watermarks
- Commercial use included
- Charged on success only
- Standard queue
Pro
$29.9
330 credits · $0.091/credit
For creators who generate clips regularly. Better value for daily workflows.
- Everything in Starter
- Better per-credit rate
- Credits never expire
- Priority queue
Scale
$49.9
600 credits · $0.083/credit
Best for marketing teams and content pipelines. More generations at a lower per-credit cost.
- Everything in Pro
- Stronger per-credit savings
- Faster priority processing
- Priority email support
Max
$99.9
1,250 credits · $0.080/credit
Lowest per-credit cost. Built for campaigns and high-volume daily output.
- Everything in Scale
- Lowest per-credit rate
- Fastest priority queue
- Priority email support
Prices include all taxes. One-time packs — credits never expire.
Questions About Sulphur 2
SulphurAI/Sulphur-2-base on HuggingFace. The fine-tune targets limb deformation, camera jitter, and temporal inconsistency.SulphurAI/Sulphur-2-base. The repo includes all checkpoints, the LoRA, four ComfyUI workflow JSONs, and the setup documentation.Ready to Try Sulphur 2?
Generate your first clip free in the browser — no GPU needed. Or grab the weights on HuggingFace and run it locally.