Gameboy Color non oem, Mega Man Xtreme 1 video game cartridge. Game cartridge comes with a plastic protective case just like the picture shows.

Mega Man Xtreme (released in 2000 as Rockman X: Cyber Mission in Japan) is an action-platformer spin-off of the Mega Man X series developed by Capcom for the Game Boy Color. It acts as a portable bridge between the Super Nintendo (SNES) titles, specifically borrowing content from Mega Man X and Mega Man X2. 

Plot Summary

Set in the 22nd century between the events of Mega Man X2 and X3, the story follows a hacker named Techno and the Shadow Hunters (Zain and Geemel) who have hacked into the Maverick Hunters' "Mother Computer". This hacking creates a virus that destabilizes global networks and resurrects digital data of past Mavericks. X is tasked with entering cyberspace to delete this corrupt data and stop the hackers, eventually discovering that Sigma is the true mastermind behind the operation. 

Key Gameplay Features

• Recycled Levels & Bosses: The game features eight main Maverick bosses and level layouts directly adapted from Mega Man X and Mega Man X2 for the SNES.
• Difficulty Modes:
• Normal Mode: Features 4 bosses (3 from X1, 1 from X2) and the initial story path.
• Hard Mode: Unlocked after beating Normal; it features 4 different bosses and a continued side-quest.
• Xtreme Mode: A bonus scenario that allows players to fight all 8 bosses in one playthrough.
• Zero Summon: While not fully playable in this entry, players can summon Zero to assist with specialized attacks.
• Customization: X can find permanent power-ups, including armor parts, Heart Tanks to increase health, and Sub Tanks to store energy.
• Save System: Unlike most earlier handheld Mega Man titles that used passwords, this game uses an internal battery-backed save system with three slots. 

Technical Details

• Visuals & Audio: The game uses 8-bit "demakes" of the SNES graphics and music, often described as showing what the X series would have looked like on the NES.
• Controls: Due to the lack of shoulder buttons on the GBC, dashing is performed by double-tapping a direction or pressing Down + A. 

If you have any questions, please let me know!
Thanks for checking out my listing.