NSC Congratulation 4 was the 4th edition of the special Congratulations spinoff, in which nations that had participated in any edition of the previous decade (this time spanning from NSC 31 to NSC 40 inclusive) are welcomed to send their favourite entry from that decade to compete together. This edition of the spinoff series was hosted by Reignland, after they won the 3rd edition of said contest, with their NSC 25] 2nd placed entry, Zombie. Alinta, St. Lotus and Instir returned for this contest, having already withdrawn from the main contest beforehand.