For as long as there have been games there have been fans cracking them open and stuffing new levels inside them - unofficially, of course. For decades modders have been finding ways to sneak extra content into their favorite games and that's especially true of the Sonic community.
The fans of the blue hedgehog have made full-blown makeovers of existing games, or additional levels to showcase what a game could do further.
Since its release in 2017, Sonic Mania is still regarded to be one of the best Sonic games of its time, but modders have been expanding it with new levels, mods, characters, and conversions to prolong it further.
With this in mind, we've played through countless levels to highlight six of the best, from their time and attention paid, to the complete randomness of others, in how some fit perfectly for a Sonic game.
If you want to get in on the mod action, here's how to install Sonic Mania mods.
Aquatic Ruin Zone
This zone is part of a collection that has four other levels from Sonic 2, released back in 1992.
Sonic 2 Mania is a team effort to remake certain zones into the Sonic Mania engine, but with remixed music and their Act 2 variants twist what you think of what the level entails.
Released back in 2019, Aquatic Ruin Zone led the way for other modders. Rather than create a 1:1 remake of older Sonic levels, the team expanded on what came before with new sections. They look and play like official DLC from SEGA.
Aquatic Ruin Zone has been remade from the ground up, with remixed music and all the enemies intact, alongside the dangerous arrows and the breakable pillars that are across the two acts.
This zone is a great example of building on what made the level memorable while expanding upon its design.
Released as part of the Misfits Pack, you also get three other zones as part of a demo that remixes established and cut levels from past Sonic games.
The music is a big highlight here, where the drums and percussion make the track pop as you run for an oxygen bubble or jump across risky platforms.
But what makes this zone a highlight, is how much the level doesn't stay in the underground parts of the Mega Drive version. As you try to jump and run to the top of the level, you see cracks of light in the background, reminiscent of a scrapped idea for the zone that was found in a leaked beta build of Sonic 1.
Once you reach the top of the level, you find an unexpected night sky, but it works so well it feels natural.
As there's currently no way to edit or add in new bosses, you're using the same one from Hydrocity Zone Act 1, but it still fits the brief, and it makes you wonder how a new boss could work in this remixed Labyrinth Zone.
This is a level taken from the Master System release of Sonic 1, SEGA's 8-bit system released two years before the Mega Drive.
Some arguably regard the 8-bit port to be superior to the Mega Drive version, mainly due to the different zones such as Jungle Zone and Sky Base Zone, alongside the Chaos Emeralds being hidden in each level, rather than the motion-sickness-inducing Special Stages.
Instead, this mod is the best of both worlds, where you get one of the best levels from an 8-bit Sonic game, with its green and orange pixel art put together with its catchy music tune that's remained unchanged, and rightfully so.
Available as two acts, with the second act offering a sunset theme, it's a level that's asking to be remade in a future game.
Hill Top Zone
We're slightly cheating here, as this is part of the Sonic 2 Mania mod that has Aquatic Ruin Zone in this list. But when you consider that there's two Acts here, completely remade, with remixed music and a twist in Act 2, it's one of the best mods you could download for Sonic Mania.
You can control other characters here as well, but Knuckles is a good fit for Hill Top, as you can glide and climb up the platforms while avoiding the lava.
The moments of being in a cave and the rising lava is all here as it was in Sonic 2, and again the two acts feel as though they are right at home in Sonic Mania. For a level that was originally conceived to be a past version of Emerald Hill Zone during Sonic 2's development, it's become iconic in 30 years since its debut and begs to be remade for a future 2D or 3D outing.
This isn't just one zone from the GBA sequel released back in 2003, but six, all working as intended in Sonic Mania.
Music Plant is part of a collection of levels from the Game Boy Advance release of Sonic Advance 2, released back in 2002. It was the second time Sonic appeared in a 2D game on a handheld other than SEGA's, with an appearance on the NEO GEO Pocket Color in 1999.
Here, there are six zones recreated in Sonic Mania, all with its original music. But it's Music Plant which is the highlight for this mod.
In one of the most colorful zones in a Sonic game, you're bouncing between piano keys while rolling down rails, all in Sonic Mania's engine. The zone's music is originally from another SEGA game called Ristar, which is also in this mod, which fits well for the design and the atmosphere of Music Plant.
But the mod is still under development, with more zones being worked on to be implemented.
Do you remember playing The Lion King in the mid-nineties, and wondered if a level could work in a Sonic game?
Wonder no more, as a talented modder has ported over the fifth level from the SEGA Mega Drive game, with monitors and enemies scattered throughout.
It's a short level, as you need to reach the top, and Act 2 requires you to get to the end in under sixty seconds.
But what sells it, is a cover of Toto's Africa that plays throughout both Acts, which just feels so right.
Its randomness is what makes this level so compelling, and while there's next to no chance of a Sonic and Simba crossover, it does make you wonder if other levels from The Lion King, or Aladdin on the Mega Drive, could also work for Sonic Mania.
- Our pick of the best Sonic fan games you can play
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Daryl had been freelancing for 3 years before joining TechRadar, now reporting on everything software-related. In his spare time he's written a book, 'The Making of Tomb Raider', alongside podcasting and usually found playing games old and new on his PC and MacBook Pro. If you have a story about an updated app, one that's about to launch, or just anything Software-related, drop him a line.