The Scottish rock band, who hit the stage before headline act Metallica, debuted new songs such as the aptly-named 'Victory over the Sun' during their early evening slot.
The group also performed singles including 'Mountains' and 'Many of Horror', the latter of which was previously covered by X Factor winner Matt Cardle.
Biffy Clyro's set coincided with a rare sunny spell at Donington, following two days of severe wind and rain.
The weather caused major delays in traffic on Friday, and extremely muddy conditions across the festival site.
This year marks the tenth anniversary of the Download Festival. Headline acts include The Prodigy, Metallica, Slash and Black Sabbath.
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