Over 100 new solutions to the popular Vietnamese puzzle game Evereto – but now more often referred to by the name of the game's creator, Tri Uan, – have been published in time for the millennial anniversary of Hanoi, according to Uan's son, Nguyen Tri Hung.

The game helps sharpen powers of observation through the discovery of resemblances between geometric and natural forms, such as a face, a lotus, a horse, a bird and a heart.

Hung told the English-language daily Vietnam News that the new answer book guides players to form various figures from seven basic wooden pieces to resemble famous Hanoi landmarks such as the Tortoise Tower and the One-Pillar Pagoda.

The game has been popular since Uan created it in 1940.

According to Uan's daughter, Nguyen Bach Ngoc, her father took part in revolutionary activities from a very young age. He was arrested by French troops in May 1940 when he was 24 and exiled in the northern province of Phu Tho. With help from his comrades, he fled to nearby Hanoi and took part in the revolutionary underground.

Uan hid himself in a lumber room at a house at 42 Hue Street in Hanoi. His only source of entertainment was to cut cartons into pieces and make them into shapes.

"My father told me that he was an excellent student of math at the Buoi High School, so he wanted to make something out of what he had learned," said Ngoc. "After several days, he had cut seven pieces from an 8 by 10cm rectangle. From these pieces, he could shape thousands of natural forms. At that time, my father named the game Evereto."

Ngoc says that the game's name was changed to Tri Uan by President Ho Chi Minh, who said that the game contained Tri (intelligence) and Uan (mystery), making the creator's name well-suited to the game.

After the restoration of peace in Vietnam in 1954, President Ho and Party and Government leaders chose Tri Uan game sets as gifts for their international friends.

The palm-sized wooden game set can still be found at educational bookstores in Hanoi for 55,000 VND (2.80 USD) or from the creator's family at 129 Phung Hung street in Hanoi, by telephone at 0904277423 or by email to tringuyentrochoi@yahoo.com.vn./.