Understanding spheres
A being such as a deity, demon or megabeast may come to represent or epitomize certain things like emotions, qualities, terrain, and items. They are called "spheres". As an example from real-world mythology, the Greek goddess Athena is goddess in the "spheres" of wisdom, warfare, handicrafts and reason.
Gods and adored megabeasts can grant secrets related to their spheres. In unmodded DF, this means that death gods can teach the secret of life and death to worshipers, turning them into necromancers.
Dwarves and other creatures will come to worship certain "powerful beings" and as such will follow that religion, and have a relationship with that "deity"
Available sphere tokens are:
AGRICULTURE ANIMALS ART BALANCE BEAUTY BIRTH BLIGHT BOUNDARIES CAVERNS CHAOS CHARITY CHILDREN COASTS CONSOLATION COURAGE CRAFTS CREATION DANCE DARKNESS DAWN DAY DEATH DEFORMITY DEPRAVITY DISCIPLINE DISEASE DREAMS DUSK DUTY EARTH FAMILY FAME FATE FERTILITY FESTIVALS FIRE FISH FISHING FOOD FORGIVENESS FORTRESSES FREEDOM GAMBLING GAMES GENEROSITY HAPPINESS HEALING HOSPITALITY HUNTING INSPIRATION JEALOUSY JEWELS JUSTICE LABOR LAKES LAWS LIES LIGHT LIGHTNING LONGEVITY LOVE LOYALTY LUCK LUST MARRIAGE MERCY METALS MINERALS MISERY MIST MOON MOUNTAINS MUCK MURDER MUSIC NATURE NIGHT NIGHTMARES OATHS OCEANS ORDER PAINTING PEACE PERSUASION PLANTS POETRY PREGNANCY RAIN RAINBOWS REBIRTH REVELRY REVENGE RIVERS RULERSHIP RUMORS SACRIFICE SALT SCHOLARSHIP SEASONS SILENCE SKY SONG SPEECH STARS STORMS STRENGTH SUICIDE SUN THEFT THRALLDOM THUNDER TORTURE TRADE TRAVELERS TREACHERY TREES TRICKERY TRUTH TWILIGHT VALOR VICTORY VOLCANOS WAR WATER WEALTH WEATHER WIND WISDOM WRITING YOUTH