Now, this isn't Minecraft's first crossover, but Sonic may be one of the more ambitious. Where most of these packs include a themed world, Mojang has really tried to make an honest-to-hedgehog Sonic game, crafting what sounds like a system to procedurally generate 3D Sonic maps—loop-de-loops and all.
There are ring and power-ups to collect, speed boosts and bounce maps to fling you around the map, enemies to stomp on, and multiple biomes ranging from chemical plants to the series' iconic chequerboard hills (which, admittedly, work extremely well with Minecraft's blocky look).
That said, Sonic and pals look bloody weird all Minecraft'd up like this. The artists have clearly put a lot of effort into making this work, but I'll never get over your man's cuboid spines. Couldn't hurt a fly with those things, never mind an egg-shaped supervillain.
Disclosure: I previously worked as a level artist on these kinds of DLC packs for Minecraft's console ports, several of which are now in Bedrock Edition.