Sonic Robo Blast 2 is a free 3D Sonic the Hedgehog fan-game built on a heavily modified fork of the Doom Legacy source port of Doom. It is closely inspired by the original Sonic games from the Sega Genesis, and attempts to recreate their classic design in 3D with robust multiplayer and mod support.

Features:
• Old-school Genesis-era platforming complete with rings, springs, baddies, reversible gravity and more!
• Fast-paced multiplayer action with support for up to 32 players online or 2 player splitscreen across multiple game modes.
• 3 playable characters - Sonic (Speed), Tails (Flight), and Knuckles (Power) - traversing unique stage paths and carefully balanced for online match play.
• Deep exploration spanning a variety of locations, from green meadows to deep underwater ruins, mines, mountains, and space stations - or perhaps more...
• Original soundtrack produced by some of the most renowned Sonic music artists on the internet.
• Loads of unlocks to keep you busy far past completing the single-player campaign, including hidden levels, game modes, and cheats!
• Extensive configuration support for modern Keyboard + Mouse controls, or more relaxed gamepad controls, with individual sensitivity sliders.
• Tons of user-created content - custom characters, levels, mods, and all sorts of other good stuff to extend gameplay well beyond the initial package.
• Well-supported level design tools (such as Zone Builder) that allow easy creation of your own custom stages. (See SRB2 Wiki: Level Design for more info.)
• Flexible mod support via Lua scripting or Sonic Object Configuation system - allowing new items, enemies, bosses, scenery effects and (much) more.
• Full source code for the game available on GitLab and GitHub.