During 2013, SuperMarioGlitchy4's bloopers began to get much wilder and ditzier, but also more random. Many characters started using different facial expressions through the use of texture replacement (they in fact already appeared in a few late 2012 bloopers, but very rarely); nor do all color-code-based characters' heads move back and forth, as Mario's does ingame. SMG4's YouTubers friends had started to decrease in appearances, although they still did some frequent appearances during the first half of the year. The reason of this dercease is that SMG4 decided to focus more on official characters, especially the Mario characters, rather than YTbers, because as those official characters aren't real, he can freely insult and abuse them, while doing this with YTbers could lead to conflicts, as they're real life persons. Although the 2013 bloopers focus more on characters from the Mario universe, some non-Mario characters such as Steve and the Teletubbies began to appear more frequently.
During 2013, the concept of swag was introduced, and a few miniseries were created, such as The Adventures of Mario and Luigi, The Wacky Wario Bros. and Retarded64. Some fans consider 2013 to be SMG4's channel's best year overall.
SMG4 had started to add personalized thumbnails to most of his new videos. Most of those title cards were made by Kulit7215 on DeviantArt.