Lord of The Rings used some huge external green/blue screens. One I know of was the scene in Return of the King where there's a dead oliphaunt and, IIRC, Eowyn

Lord of The Rings used some huge external green/blue screens. One I know of was the scene in Return of the King where there's a dead oliphaunt and, IIRC, Eowyn fighting the Witch King. But there were lots of others.