A retired house painter in Britain, who has chosen to remain anonymous, reportedly sold his collection of Pokémon cards for £1.56 million at auction. The collection began with cards saved by his son in the late 1990s and eventually grew to 42 complete sets, some of which had remained unused and in excellent condition in the attic for about 15 years.

The most valuable set, the Legendary Collection Complete Master Set, had been estimated to fetch between £15,000 and £20,000 but sold for £100,000. The auction house said the collection’s total value made the sale its most lucrative to date.