Largest videogame ported to the Sinclair ZX81

According to Official Guinness Records,

The largest videogame ported to the Sinclair ZX81 is Dragon's Lair at 15,824,610 bytes, achieved by Jim Bagley (UK), in Merseyside, UK on 30 April 2015.Dragon's Lair is a retro classic arcade laser disc game, where it plays a movie of Dirk the Daring rescuing princess Daphne from a dragon.

For a complete list of 2015 records, please visit 2015 Guinness Records in United Kingdom.

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