Can You Mod Fallout 3 on Xbox 360 Using a USB and the G.E.C.K.?

No. You cannot mod Fallout 3 on Xbox 360 using a USB drive and the G.E.C.K. (Garden of Eden Creation Kit).

Why It's Impossible

• Closed Platform: Xbox 360 is a locked ecosystem; Microsoft controls all executable code.
• No Console G.E.C.K.: The G.E.C.K. is a PC-only tool for creating mods; it was never released for consoles.
• Limited Modding: The only "modding" on Xbox 360 involves modified save files (often adding items/stats), which is far less flexible and can corrupt saves.

Alternatives

• Xbox 360: Use pre-made modded save files from community sites (use at own risk).
• PC: Full access to the G.E.C.K., Nexus Mods, and Steam Workshop for unlimited custom content (items, quests, graphics overhauls).

For a true modding experience, the PC version is the only viable platform.