It's in the extra material that Old World Blues really makes its mark. New tools and weapons are casually dropped into the world, often so useful that you'll wonder how you got through the game without them. The Protonic Inversal Axe carves through robotic enemies like butter. The K9000 Cyberdog is a brutal machine gun that literally barks and snarls. There's a Sonic Emitter weapon that both plays a vital role in the story, and disintegrates force fields and fries electronic foes. In a nice touch, you can augment its abilities by finding new sound recordings, from opera singers to the screams of a giant tarantula.
And this is just the tip of the iceberg. The level cap has been raised by five, and a handful of new perks, both regular and unlockable, quickly prove beneficial. Them's Good Eatin' is an absolute godsend for those playing in Hardcore mode, as it gives every defeated enemy a 50 per cent chance of providing free, powerful and valuable health items in the shape of Blood Sausage and Thin Red Paste.
The plot picks up pace when it needs to, but never intrudes when you decide to follow your own muse, and Obsidian's skill at writing narrative into the scenery means that nothing is there for no reason. Whether it's a room piled high with Mentats or a test chamber based around a high school, you'll always understand exactly what it means for one or more of the characters. Even something as simple as picking up an old dog bowl can send you off on a side quest that deepens your understanding of the motivations and rivalries slowly bubbling to the surface.
Usually with these downloadable packs, it's easy to summarise the goodies that players will take away at the end, but in the case of Old World Blues there's simply too much to consider. There's a small, automated apartment, The Sink, that contains nine appliances, each with its own personality and benefits. Revive and upgrade the toaster and it will somehow create a fearsome melee weapon for you.
There's an Auto-Doc that will heal wounds, change your features and install body modifications. A roaming robot called Muggsy has a mug obsession and will exchange these useless items for energy ammo and scrap electronics. Even the light switches (two of them, locked in a bitchy rivalry) can alter the ambience to give long-lasting status boosts.
You never once interact with another living being during Old World Blues, yet it has more personality and wit than any of the previous DLC offerings. Every conversation is a joy, and the voice acting really helps to sell the idea that a Biological Research Station would talk like Barry White and drawl seductively about giving up some seeds.
It all adds up to the strongest expansion in the relaunched series, across both Fallout 3 and New Vegas. The story alone takes a good six or seven hours to play through, and even then there's still enough juice in the tank to warrant a few more just poking around and finding new things. Best of all, it fleshes out the past and teases about the future, setting the stage for Lonesome Road and the end of the Courier's journey.