If you need help finding a safe download link or setting up a Flash emulator: Check out the Flashpoint Archive. Visit the Exploding Rabbit community Discord. Look for standalone "SWF" player tutorials.
Since Adobe Flash was officially discontinued, playing the original browser version can be tricky. However, the gaming community has preserved Super Mario Bros. Crossover 3.0 through several reliable methods.
Character Skins: Choose between the NES, Game Boy, or Super Nintendo versions of Bill Rizer. Conclusion
Directional Aiming: Unlike Mario, Bill can shoot upward and diagonally, making short work of Lakitu and flying Cheep Cheeps.
Exploding Rabbit Official SiteWhile the original web player may not work in modern browsers like Chrome or Edge, the Exploding Rabbit forums and official site often provide standalone executable files (.exe for Windows or .app for Mac). These "projector" versions don't require a browser to run.
If you are looking to relive the glory days of 8-bit action, here is everything you need to know about the Super Mario Bros. Crossover 3.0 Contra experience and how to get it running today. The Ultimate Retro Collision
Expanded Roster: Play as Mega Man, Samus Aran, Simon Belmont, Link, and Ryu Hayabusa.