He developed his artistic talent under the guidance of his parents and attended the Shevchenko State Art School in Kiev, where he graduated in 1975.

[1] During the repressive Soviet period, when artists needed state approval to exhibit in official galleries, he participated in underground art shows.

[2] During his childhood, Kostetsky began to create a distinctive style based on his love of mysterious alien civilizations and science fiction.

At school he worked on sculpture, learning from his sculptor mother, and in the seventh grade he created a set of chess pieces intricately carved like medieval knights.

At the same time he developed his own style and technique of oil painting, wishing to capture his unique artistic visions.

However, while studying at the institute, the young Kostetsky had to obey to the canons of socialist realism and his early works do not always reflect his true interests.