Thief: Deadly Shadows - Shalebridge Cradle Part 2 of 3 

I love that, especially when you're lock picking because it adds a whole new level of tension. You can't take you attention away from the lock while you're picking it, but you know a zombie is nearby and he may have just spotted you.

Flashbombs, Explosives, and Fire Arrows--you need to gib zombies, in the earlier two installments, though--just knocking them down won't kill them for good. As for Ghosts and Hammer Haunts, you can kill them with your sword. In fact, ambushing a Hammer Haunt with a fully charged sword swing is a good way to save flash bombs. Deadly Shadows Holy Water is also an instant kill on all undead types.

I think of it like 1800's London, except they have electricity.

The setting of the Thief mythos is a place called 'The City'. It doesn't go by conventional real-world dating or geographical placement, and features a lot of anachronistic technology, like cybernetic eye implants, electric lights, radio antennae, magical street-lamps that seem to run on some kind of contained plasma substance, and coal-furnace-powered steam robots and turrets. Your best bet at dating it is going to be based on the armor style and patterns of various guards, the interior architecture of certain buildings, and the Hammerite sect, which draws some rough analogues with the Catholics and Freemasons. There's also the Precursor Masks, to compare to. Might be worth some kind of RU-vid theorycraft, at some point, to look into. I personally like to think Thief is set in some kind of alternative-history magical Dark Ages, where the Dark Ages came about as a result of a magical Pagan-induced zombie plague, that threw the church into complete disarray, broke their power over the ruling class, and spawned the need for enhanced technology and the development of religious exorcismal magic to thwart the supernatural undead menace. As a result of the competing magic cults, you have a lot of entrepreneurial inventors and pirate mercenary gangs springing up where they'd once have been oppressed by the Hammerite church--and the Keepers just kind of hang in the shadows containing the various conflicts between the Pagan and Hammer sects, gradually allowing the city to continue being the weird place that it is, because the alternative would be too much order or too much chaos. Basically, a premature medieval industrial revolution sprung up, out of a need to fight and contain Pagan zombie magic. But then, this is leaving aside the fact that some portions of the Thief series take place in what seems to be another dimension entirely--the Maw of Chaos, which seems to be some kind of nature-based Hellscape full of nasty cannibal beast-people and murderous human-hating ents and dryads. I doubt you can really date something like that.

@@GoldieTamamo Really good answer.