Tools used
Requests
Requests can be made, within reason, for certain scenes to be rendered (a scene from a piece of fan-fiction, for example) and will be completely free. However, the models themselves will not be uploaded in any format. Requests for any model from the game to be rendered in any pose from either game will be completed as soon as possible, bearing in mind that human heads can't be done.
Author
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Troodon80 - As the author of the reference sheets, all I can do is hope that they are at least somewhat useful to someone; whether that be to make a costume, a model prop, a figurine, or drawing some fan art. So far, the list contains over a hundred reference sheets and it's still unfinished.
Copyright
All references are free to be used by anyone, linked by anyone, and altered by anyone. No credit is required. No permission is necessary. All characters, animations, and textures (with the exception of one) in this list are owned by BioWare/EA. No copyright infringement is, or was, intended.
has rendered a number of references with the hope of helping other artists, this is currently still ongoing. While not technically fan-art themselves and thus cannot be submitted to this group, hopefully this blog with links to the references will help others. They cover a range of angles which may be difficult to see in-game -- or are, in some cases due to lighting or camera angle, almost impossible to see.
The characters from the games are generic unless otherwise stated. So far, they also cover all major characters from both games. Human NPCs are difficult to render due to the morphing technique that BioWare has used. In this regard, Commander Shepard will be default for both genders.
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