Great OVA compilation from Go Nagai (永井豪) robot family which i found on youtube :)
Go Nagai was born in Wajima City on September 6, 1945. He was inspired to become a mangaka (manga author) after his brother gave him a copy of Osamu Tezuka's Lost World. Since that day, Go Nagai pursued his dream of becoming a mangaka.
Simultaneously to Mazinger, he created one of his most popular series, Debiruman (デビルマン, Devilman), about a demonic hero fighting against hordes of demons. Nagai also turned Devilman into a manga which was more violent and gritty compared to the original.