The Super Meeseeks Bros. tee design is for Rick and Morty and Super Mario Bros. fans that can't decide which to spot on their shirt.
The concept is a mash up of Super Mario Bros. 3 and Cartoon Network's Rick and Morty character Mr. Meeseeks. This is not the first nor last mashup of these 2 franchises as the Tiny Rick tee variations for example have proven to be popular.
As for the artwork, the coloring is accurate for the Rick and Morty cartoon but the style is a decent marriage of both franchises as it has some strong Mario elements as well. There isn't much in regards to shading but as for most designs it isn't needed anyway. The golf clubs carrying caddy version Mr. Meeseeks is the best Meeseeks reference so it works out perfectly.
Wear this anywhere casual attire is the norm.