Recently, an enthusiast going by the handle Cobalt unveiled a massive project: with its help, players can now play through Fallout 3 and Fallout: New Vegas inside Fallout 4 (which can also be completed). Traveling between worlds is available at any time.
The modder brings equipment, weapons, unique items, creatures, and other elements from previous franchise installments into Fallout 4. Certain mechanics were adapted for the fourth game; for instance, they “created a map plugin for the Pip-Boy that plots a path to the destination just like in the original Fallout 3, through the subway.”
The modder warned that some bugs might have slipped through during testing:
This is a massive project that I’ve been passionately working on for a long time. We extensively tested and fixed bugs in the main storyline, side quests, and DLCs of both games across multiple FO4 versions and different playthrough setups. More than a dozen full playthroughs were completed. And it seems we have finally reached the point where the main bugs are ironed out and all games are quite stably playable. I suppose some bugs might still remain somewhere.
The mod “Fallout 34 (Fallout 3 and NV in Fallout 4)” for Fallout 4 is distributed free of charge via Nexus Mods. Game files are not included in the archive; it is merely a converter utilizing files provided by the players.
For the converter to work, all games must be installed in separate directories before running the installer. According to the modder, the conversion process can take around 2 hours.
The installation process has deterred some players; for example, Dr_Nefario4 remarked: “Looks like you need a PhD in bug troubleshooting just to install everything properly.”
There is also an optional mod titled “Fallout 34 Online”, which is compatible with this project and introduces multiplayer elements: players can see other users running the mod and interact with them; online events will also be available. In addition, local co-op has been implemented.