A superb beat'm up that improves upon classics as Turtles in Time and Hyperstone Heist.
Shredder's Revenge has wonderful pixel-art, levels filled with fun references to the 1987 TMNT tv-show and smooth gameplay that's stupidly fun.
The game offers a story mode and an Arcade Mode. Story mode let's you play through the game while leveling your characters. There are some collectibles and optional challenges in each level. Arcade Mode let's you battle through the levels for a high score in the leaderboards.
While Shredder's Revenge is fairly short (16 levels that each take 5 to 10 minutes) there is a lot of replay value. The seven characters feel different enough to justify multiple playthroughs and that's not even counting the hours you can spend in both local and online co-op.
The DLC added even more characters and a survival mode. While survival mode is not as good as the one in Streets of Rage 4 it's still fun to play around with. The only real downside I can think of is that the game is not on GOG. Let's hope that mistake gets corrected soon.