There are many kinds of slavery, and many, many slaves. The Tammuz are from a line of created beings that were slaves, but now, have chosen to rise above. They are born from the Earth and the Divine Fire pushes them to become more than just tools.
For more information, look into Promethean: The Created, Page 110.
The Golem tend to remain on the fringes and lower strata of human society, looking much like slaves in their choice of modern dress. At least one tattoo, piercing or body modification may be found upon every one of them; part of the traditional Tammuz process of Rebirth insists that the Maker add such a detail to the corpse as a reminder of their Lineage's origins as slaves, though they may acquire additional such markings later. Also, they choose durable, work clothing, looking like auto mechanics, plumbers, miners and the like.
The Tammuz are created from the earth, and look like it. Clay lumps on and inside their flesh, and they are built like stones. Bloodless cracks run deep into the skin and overall, they merely look like clay dolls. In addition, some have powerful trait-words etched into their forehead, which glow with an epheremal fire to Azothic sight. These words (usually abstract concepts such as "Truth", "Death", "Hope",) may be written in any kind of script, recognizable or not, or they may be Promethean sigils with more layered meanings. The wize Tammuz bearing such marks protect them, as changes to such marks may have serious effects upon their bearers, up to and including immediately going into Torment or helpless immobility.
Bestowment: Unholy Stamina
Above all, their slavery has taught Tammuz to be tenacious. In terms of the game, a bonus is granted to their Stamina based rolls and they may spend Pyros to re-roll a failure. This is almost exactly like the Frankenstein Bestowment of Unholy Strength.
Alternate Bestowment: Unbreakable Will
Despite their origins as slaves, every Tammuz is also made to seek freedom. Perhaps meant to strengthen themselves through constant struggle for control of their own fates, some Tammuz acquire a drive to be free that is as unconquerable as the Azothic Fire itself. In game terms, this Bestowment grants the '9-again' rule on any Resolve-based rolls; spending a point of Pyros allows a re-roll without the 9-again benefits. Also, the Tammuz Resolve is doubled for purposes of resisting a supernatural attack, such as a Promethean Transmutation or a mortal's Numina.
Control and Curiosity. The Tammuz inspire the need to control them, or at least figure them out, in the humans that are afflicted by their Disquiet. They must fight to maintain their physical freedom from these now-fanatical humans.
While all Created should beware of the mortal friends and relatives of the corpse (or corpses) from which they were made, Tammuz face an additional problem. The nature of their Disquiet makes those who seek their mortal precursors refuse to believe that the Created are anything but their lost loved one; a victim of amnesia or some other malady, but the same person, nevertheless. Investigators and family members will expend great effort to bring the Tammuz 'home' and re-integrate them into a life that the Tammuz can neither remember nor fulfill. Even when confronted with Tammuz Disfigurements and a spectacular show of Transmutations, the Tammuz' unwanted social circle will be more likely to destroy them (in the name of setting them free of the 'unholy changes' they have undergone), than to allow them to get away and pursue the Great Work without further hindrance.
With the exception of the Uratha, most other supernatural societies in the World of Darkness will follow similar paths upon encountering a Tammuz. While a Wretched will probably be seen as a threat from the get-go, and a Galateid might be mistaken for a suitable lover (or appealing snack for the Kindred), supernaturals are slighly more likely to try and recruit or enslave a Tammuz at the first hint of the power that the Promethean wields. After all, the story of Rabbi Loew and his golem is somewhat better known among the Awakened than in Sleeper society, and the Kindred are always looking for a new tool to gain an advantage over their rivals.
Lineages from Magnum Opus::
Lineages from Saturnine Night::