Altars are religious structures that allow you to interact with the various gods of Crawl. Each altar is dedicated to a single god. You can convert to a god's religion by praying (command <) at their altar. When you do this, you will be shown a description of the god and asked if you're sure you want to worship them, just in case. Altars are irrelevant to a religion once you've joined it.
Worshiping a god will provide you with several useful abilities, but usually comes with an associated cost or set of restricted actions. Failing to follow your god's code of conduct will result in being stripped of your benefits until you've made penance; you may also have to deal with divine retribution. As such, make your choice of god carefully.
| A shattered altar of Ashenzari.
This crystal altar shattered to pieces when Ashenzari was cursed. But still, there is power here: a dark aura holds the shards in mid-explosion, suspended in time and space much like the god they herald.
| A roughly hewn altar of Beogh.
An altar to Beogh, unmistakably roughly hewn by orcish artisans.
| A snail-covered altar of Cheibriados.
This altar seems somehow more stationary than the others.
| A shadowy altar of Dithmenos.
This altar to Dithmenos the Shadowed seems to absorb light from its surroundings.
| A white marble altar of Elyvilon.
An altar to Elyvilon the Healer, made from purest white marble and topped by a sculpture of the Chalice of Purification.
| A blossoming altar of Fedhas Madash.
An altar to Fedhas Madash, covered in vibrant and colourful plant life.
| An opulent altar of Gozag.
This glittering golden and bejewelled altar to Gozag Ym Sagoz the Greedy gleams brightly, even in the dim dungeon light.
| A hazy altar of Hepliaklqana.
An altar to Hepliaklqana the Forgotten, shrouded in mist and difficult to make out clearly. Something about it seems terribly familiar, but it's impossible to say exactly why.
| A viscous altar of Jiyva.
A slimy, ever-shifting altar to Jiyva. You're not sure what it's made from, and you don't really want to know.
| An ancient bone altar of Kikubaaqudgha.
Ancient bones were piled here to form an altar to the terrible Demon-God Kikubaaqudgha.
| A corrupted altar of Lugonu.
An altar to Lugonu the Unformed, possibly dedicated to some other power before it was irrevocably corrupted.
| A burning altar of Makhleb.
An ever-burning altar to Makhleb the Destroyer. Strange, twisting shapes are visible in the flames.
| A sparkling altar of Nemelex Xobeh.
This altar sparkles with a lightshow greater than any gambling den's to attract followers for Nemelex Xobeh.
| An iron altar of Okawaru.
An altar of iron and steel dedicated to the Warmaster Okawaru. Its edges are surprisingly sharp.
| An oddly glowing altar of Pakellas.
Strange, half-completed devices, tools beyond your comprehension, and a persistent light glowing in odd colours all adorn this altar to Pakellas the Inventive.
| A stormy altar of Qazlal.
Fierce winds, electrical discharges, puffs of fire and magma, and the occasional tremor surround this altar to Qazlal Stormbringer.
| A sacrificial altar of Ru.
An altar to Ru the Awakened in the shape of a scales with a heart in one scale and a pictogram representing power and enlightenment in the other.
| A deep blue altar of Sif Muna.
An altar of the deepest blue, covered in intricate patterns and writings in long forgotten scripts, devoted to Sif Muna the Loreminder.
| A bloodstained altar of Trog.
An altar to Trog the Wrathful, crudely made by what seems to be the hands of giants and covered in bloodstains
| A hide-covered altar of Uskayaw.
An altar to Uskayaw the Reveler. It appears to be hollow and covered in a hide, giving it a resonant surface. Carvings on the side depict grouped figures that could be dancing or loving or fighting.
| A radiant altar of Vehumet.
An altar, ablaze in the lights of Iskenderun and promising great destructive powers to those who would follow Vehumet.
| An ornate altar of the Wu Jian Council.
A red and gold altar to the Wu Jian Council. Sharp slivers of steel drift through the quiet air surrounding it.
| A shimmering altar of Xom.
This altar constantly shimmers in all visible colours and probably some invisible ones, too, matching the whims of Xom the Unpredictable, to whom it is dedicated.
| A basalt altar of Yredelemnul.
An altar to Yredelemnul the Dark, worked from columnar basalt.
| A glowing silver altar of Zin.
An altar to Zin the Law-Giver, made from silver as pristine as Zin's followers are expected to be, and glowing gently.
The Shining One
| A glowing golden altar of The Shining One.
An altar to the Shining One, made from the purest gold and almost blinding in its radiance.
| A faded altar to an unknown god.
An ancient altar, stripped of all identifying characteristics by the passage of time. Praying at it will convert you to an unknown god, and the altar's deity will greatly appreciate conversion at so ancient a site of worship.
Praying at a faded altar will convert you to a random god. This poses a risk, however, as the god may greatly clash with your strategy (getting Sif Muna for a melee character or Trog for a caster). To compensate, you'll begin with 20 extra piety. As their piety systems are unusual, Gozag waives the entry fee and Ru immediately offers a sacrifice.
Faded Altars were added in 0.17