Somewhat deviant from the original source material or model sheets.(adjective)
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Use "off-model" in a sentence
"They alter the designs slightly for comedic effect but never go far off-model."
"Later in the last third of the film, and especially in the last ten minutes, there are some horrible off-model faces, which pulled me right out of the film at its most climactic moment."
"Given Spongebob's morphing ability, none of those cake images are really too far off-model."