Melius

Cast is a new studio inside Melius for producing short video with AI avatars. Creators pick an avatar from a library or build their own, drop in a script, and Cast generates the finished clip with voice, background, and framing already handled. The product is aimed at anyone making digital storytelling content, from UGC ads and vlogs to podcast segments, microdramas, and short films, with a fill-in-the-blanks interface meant to replace the usual chain of separate generation tools. Cast ships on Melius, which bills itself as the AI-native operating system for creatives and routes work through an agent called Mel across every supported model in one place . The underlying platform taps a broad set of third-party models, including image models like Nano Banana, GPT Image, Flux, Seedream, and Ideogram, plus video models like Seedance , so Cast users can swap engines without leaving the workflow. The launch matters because avatar video remains one of the most fragmented corners of generative media, and Melius is pitching a single surface where a script becomes a watchable take. Melius is built in New York by co-founders Joowon Kim, Young Kim, and Arnav Ramu, who met as engineers at Ramp before starting the company. For launch, Melius is offering up to $50 in credits to new users who sign up for a paid plan, giving operators and creative teams a low-friction way to test whether avatar-led content fits their production pipeline.