once, playing with Anomen in my party, I got him to level 25 and he received a holy symbol of helm. this gave him +1S and some extra spells.
Do all Clerics (Viconia, Aerie, PC cleric) get this at level 25 or is it exclusive to Anomen?

<font color = shadowed cyan> all clerics get this itemwhen they reach level 25. Its part of the Throne of Bhaal add ons or whatever you want to call them. </font>

Another Question, does the effect of the item vary according to cleric. I'm assuming Viconia will get a symbol of Shar and PC a symbol of whichever god they devote themselves to. What about Arie, I don't remember any dialogue from her hinting as to what Elven god she is a cleric of?

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Without mods, good clerics will get Symbols of Lathander, neutral clerics will get Symbols of Helm and evil clerics will get Symbols of Talos. Mods change this (I believe Divine Remix and Ashes of Embers), but in the base game they all have the same effect.

But I believe, although their effect is same they are worn at different places? Lathander's as a ring while Talos a necklace?

Just on a side notice. If Anomen fails his test does he get the symbol of Helm?

Nope, they're all rings.

Which is sort of a bummer in a "lack of originality" kind of way.

And I think that Anomen will get the symbol of Helm if he fails. I think the game determines what ring you get by what alignment you are *when you reach* level 25.

so Viconia will get Talos? that doesn't seem right
does anyone know what the other holy symbols do?

All the symbols are exactly the same except in name and what they look like. Kinda depressing, really.

Aerie gets the Holy Symbol of Baervan, one of the Gnomish gods. I think the dialogue talks about her becoming a devotee of Baervan because of "Uncle Quayle". She has been essentially self-exiled from her people since losing her wings.

BTW, has anyone ever "traded" the holy symbols between characters? I seem to remember once that I had a game where Aerie died and I gave her Holy Symbol to Anomen, who had passed his test of knighthood but not yet received his Holy Symbol. Surprisingly, I was able to equip the Holy Symbol of Baervan but later when I reopned Anomen's inventory it had changed to Lathander. Has this happened to anyone else?