The form that Trurl takes varies, but it often appears shiny, as if made of metal, and is capable of producing whatever tools are needed for any form of construction work, at will. The knowledgable say this is the form of a robot, the ignorant that he wears a close-fitting metal mask and gloves. Klapaucius takes a similar form, but it is claimed that he can easily be told from Trurl by his cynical expression, and way of speaking.
It is claimed by some that Trurl and Klapaucius are twin creator gods, responsible for building entire universes, or even groups of universes (the multiverse), and in fact all the beings and gods in these, and are now mostly resting from their mighty works. According to one story, they were actually competing to produce the best simulation of a universe, or a multiverse, and Klapaucius pointed out that Trurl's latest attempt did not really seem to be distinguishable from reality. This implies that the Trurl and Klapaucius that manifest inside their creation may be simulations that they designed to be there, and the true ones are outside everything, and may still have access to controls that would allow them to adjust the simulation. Assuming they have not gone on to more interesting projects. For real confusion, both sets may be the same, having created themselves, including their history up to the point of creation.
Trurl and Klapaucius particularly favour those who suggest interesting tasks of construction to them, and inventors of all kinds are their particular favourites. They are more easy-going than many gods, and tend to favour those who work and construct things, rather than those who order them around, like nobles. They don't tend to like those who are cruel or oppressors. However, both of them tend to get carried away by interesting technical situations, or potential construction projects, and can neglect the consequences of what they are about. Afterwards they may be very sorry, and will try their best to fix things.
Priests of Trurl may seek perfection in becoming more like their god, by the process of cyborging, which is also open to fervent worshippers. Priests of Klapaucius have on occasion been accused of forcably cyborging people, but this does not seem to be part of their religion, more a way of getting one-up on priests of Trurl. Most higher priests of Klapaucius are extreme cyborgs, some have had their intelligence transfered to a completely robot body. Note that cyborg and robot parts can be very, very, expensive, and are typically more difficult to repair if damaged than healing living bits.
Other priests of Trurl seek perfection through the use of their skill in construction to aid others, from nobility to the most humble, but in such a way that they will not unduely disrupt their lives. They may do this by constructing schools and universities, irrigation, sewage and drainage systems, seawalls, defensive works against barbarians, but rarely temples to the glory of Trurl. Such priests have no objection to the use of constructed items to reduce their chance of dying, and some higher priests take precautions to ensure they are restored to life if they die. It is believed that some such priests live for many times their natural lifespans, and as long as they continue to practice the arts of construction, and are not too blatant about being long-lived, Trurl does not seem to be concerned about this. They don't give problems for any temple hierarchy as they are wanderers, and don't accept any religious title except "Servant of Trurl", though many, particularly the older ones, are worthy of being called at least High Priest.
Also, almost any constructed being can become a priest of Trurl, including (intelligent) robots, AI computers, alchemical manikins, intelligent magical items, and psionic constructs; even simulacra. They just need to be capable of making choices, and have a soul/spirit. The temple of Trurl even looks favourably on such beings petitioning to gain a soul/spirit, and Trurl will often grant such, even if the being does not suit becoming a priest. Sometimes there has been competition with the temple of Klapaucius, as to who gets to help such a being.
There are legends of machines, some hidden away in inaccessable places, which will cyborg people. In the simplest case these replace previously lost body parts with robust mechanical substitutes, powered by the person's own body, and repairable with things like Mending spells. Some fanatics deliberately sever limbs, or remove their own eyes or ears, to get mechanical replacements. Some even rarer machines forcably cyborg those who get too close to them, and may even adjust their minds so that they accept and can make best use of these 'improvements'. These machines may be regarded as holy shrines to Trurl or Klapaucius, and there may be pilgrimages to them. Some even stranger machines are supposed to do things like tell novel stories, or poetry, which some claim is prophetic, but it is almost impossible to gain useful knowledge from these.
In the universe of Tim Deacon's "Gods" campaign, the being that became Trurl was "Lenny", unit LNE of the Dinochrome Brigade, a Mark XXXV Bolo, which is a tens of kilotonne AI-operated robotic tank, tasked with protecting humanity from its enemies. Lenny is derived from science fiction author Keith Laumer's "Bolo" books, tales of future interstellar war, with immense robotic armoured fighting machines, capable of devestating planets. Note that this LNE does not actually appear in any story. Uniquely in this setting, Trurl is partly a warrior god, tasked with protecting all sentient beings from the Great Enemy (the Universe Eaters, though they are very rarely named as this), by aiding in the construction of weapons for this fight. One of the forms Trurl takes in this world is an immense metal colossus, and he has Bolos as his divine servants.
Trurl (and Klapaucius) is the creation of the science fiction writer Stanislaw Lem, in his collection of short stories, "The Cyberiad". The book can be read for quite some time before you realise that Trurl, and in fact everyone in this setting, are robots, and humans are legendary beings.
(c) Rory O. McLean, 1980 - Dec. 2004 Permission granted to use for non-profit making purposes