Lenya detects magic on the two symbols, avoiding the Obelisk.
Both of the symbols radiate strong magical auras. Looking at the Black Sun symbol causes you to be disturbed and on edge (Necromancy aura). The two-tiered inverted Ziggurat does not affect you (unable to identify the aura). Lenya also detected a strong magical aura on the gate. Lenya detected magic on two weapons the Cultist carries, a short sword and a dagger (minor magical auras, probably +1 weapons), as well as a third minor item she could not see.
The cultist comes over, stands on the Black Sun symbol for a minute, then walks to the the inverted pyramid symbol and stands there for a minute. The Cultist is mostly silent, but you hear him mumbling something about "the Dark Lord." Even the Cultist looks uncomfortable when approaching the Black Sun, and when standing on it, he appears to be under some stress, emotions scurrying across his face. While standing on the two-tiered Ziggurat symbol, he draws forth his dagger and looks at it and flips it over and calls out loud, "Festrath serves the Dark Lord". The cultist then goes back behind the stone column and returns to whatever he was doing before.
Lylamwyn isn't sure, but he thinks the Black Sun causes mental instability, and standing on it might drive someone insane (Spellcraft check 16+14=30, Knowledge Arcana check 17+12=29). Lylamwyn is not sure what the upside down black ziggurat is meant to do, but he believes it is called an "Obex" and it was one of the symbols of worship for one of the Dead Gods of the destroyed Suel Imperium, an evil deity known as Tharzidun (Spellcraft check 13+14=27, Knowledge Religion check 16+6=22).
Does Lenya or anyone else touch or stand on either of the symbols?