FFfffffinally!
At last! In early 2018, there appears a NEW tee with modern Sonic on it at Target stores. And, to make things better, it uses special paint & looks different and fresh by bringing an all new style! It's an all blue tee with running forward modern Sonic. However, the colors used are applied in triangles, making it look like 'glass fragment' or some sort of geometric art. Then, the shirt uses shiny, slightly puffy paint over the regular colors (but only on certain triangles) to enhance that 'glassy' type of effect. The paint may be slightly sticky or 'tacky' to the touch, but it's not frail like some metallic paints. The triangle style, nice blue color & paint effects makes this shirt a fine return to form for modern Sonic after the Boom ban. It should be around 9 dollars in the boy's section at Target. 

 Owned by Princess PandaLover

Now here's a bit of an odd tee...
It's a merchandise mash-up because it's a tee shirt...that's based on Archie Comics Sonic art. Archie was really good about minding it's property (the pages) and keeping it to paper products only. However, apparently they did allow for 1 tee which you can see here. It takes panels from lots of different issues, but you can see them clearly mentioning Knothole & recognize the artists' styles. The panels are all gray/white while Sonic 'jumping through' the center is in color with a yellow background. It makes for a dynamic design & is nice and different! This was sold at Sears before the Boom ban. 

 Owned by Princess PandaLover

This is a K-mart exclusive gray tee.
It's actually really cool because it features so many different characters. Their chosen art is really nice, and each one is in a rectangle panel, but with parts of the character 'popping out of' the panel for added interest. You can see Sonic, Eggman, Tails, Amy, Shadow, Metal Sonic, Knuckles & even Big the cat. "Sonic the Hedgehog" is in large white letters in the center of the panels. Each character has their name below their art as well.
With so many colorful characters, general appeal, & good design this is a nice shirt to have for sure. It's too bad there are not that many K-mart stores remaining.

 Here's a shirt with lots of detail!
This is a Sonic Forces tee in dark navy blue or black. The front has the 2 star symbol for the hero side & sihlouttes of the 'good guy' characters including both versions of Sonic. The back has the globe with chains, claws, ribbons & Eggman symbol over sihlouttes of the badguy characters. These include Zavok, Eggman, Infinite, Chaos 0, Metal Sonic & Shadow.
Notice the sleeve: it also has the Forces logo as well as the copyright. The paint for the designs is not applied evenly / looks 'rolled on' or 'stenciled in' which is not 'weathering', and gives a slightly different effect that's still not solid. The shirt was likely intended to look 'rebellious'. It was sold in Sega's online shop in the USA a few months after the release of the game, but where else was it sold? How much did it cost? Stuff with lots of designs like this is neat to see, but harder to make.

Another Sonic Forces tee, another sort of grim 'military' style item.
This one is called the "Special Ops Bootcamp Tee". It comes only in this grayish color you see here. The design is fairly subtle, being a monochrome slightly lighter grayish color & using only symbols/sihlouttes. It says "Special Operations Unit" at the top, which has a lightening bolt symbol on each side. There's an Eggman face in the center as the largest graphic, then Tails, Sonic & Knuckles character sihlouttes spaced between the bolt tips. The whole thing is in sort of a shield shape, maybe to make it look like a type of badge. Where is this sold? It is a 2018 summer item.