In Concept art & 2D assets, Retro Diffusion ranks #1 and Runway ranks #8. No independent quality tests found. Ranked on game-dev fit: commercial use allowed; Godot, Unity, Unreal integrations; API and official MCP server.
Commercial use: both commercial use allowed (Retro Diffusion terms; Runway terms).
Free plan: Retro Diffusion: free trial or credits only (Free starting balance for new accounts) pricing. Runway: free trial or credits only (125 one-time credits) pricing.
Shipping free-plan output in a paid game: both allow it, per their published terms.
API and MCP: both: public API, official MCP server.
Engine integrations stated by the vendor: Retro Diffusion: Godot, Unity, Unreal. Runway: none stated (standard file export).
Pixel-art-specific image models for sprites, tiles, tilesets and animations, plus low-poly 3D model generation with export for Godot, Unity and Unreal. Also sells an Aseprite extension.
AI video, image and audio generation (Runway Gen-4.5 plus third-party models), usable for trailer shots, teasers and marketing material.
Verdict
For pixel-art devs who want pay-per-image pricing with no subscription; the site says all output is yours for commercial use.
For generating trailer and teaser shots; the terms don't restrict commercial use of outputs, but Runway may train on your inputs and outputs.
Tasks●
Concept art & 2D assets, 3D model generation
Trailers & marketing, Concept art & 2D assets
Engines●
Godot, Unity, Unreal
Any (standard file export / engine-agnostic)
Free plan
Free trial or credits only Free starting balance for new accounts
Free trial or credits only 125 one-time credits
Pricing
Pay per generation from a prepaid balance: images from US$0.03 (RD Fast), US$0.06, US$0.18 (RD Pro); animations from US$0.07 per clip. New accounts get a free starting balance. source
Free $0 (125 one-time credits). Standard US$12/month, Pro US$28/month and Max US$76/month, billed annually (US$15, US$35 and US$95 billed monthly). Gen-4.5 uses 12 credits per second of video. source
Export formats
Not stated by vendor
Not stated by vendor
Commercial use
Commercial use allowed Official FAQ: "Everything you generate is yours, for personal and commercial projects alike." source
Commercial use allowed Terms of Use 4.4: Runway does not claim ownership of Inputs or Outputs and does not restrict your commercial use of Outputs. Inputs and Outputs may be used to train its models. source
Rows marked ● differ between the two tools. Licence badges: green = commercial use allowed (including any free plan or trial), amber = paid plans only, restricted, or allowed but with no free plan, red = not allowed, grey = not stated by vendor or not applicable. Read the vendor's current terms before you ship.
