Hello, sorry if this has been covered already, but what exactly is the Sigil Spell and what's Shekelor's deal (not to mention the ancient wizard who preceded him)?
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Please be aware that the answers to those questions constitute spoilers for the Faction War module.
If you've got Faction War, you've already got as good an explanation as is forthcoming, but...
The Sigil Spell was a spell that was scribed somewhere in the Cage. It was cast by following a prescribed route through some of Sigil's streets and saying an incantation. It was suposed to alow the caster to modify Sigil, and through Sigil the Lady. In practice, no one could walk it because the Lady would stop them. At least, up until the Faction War, when the Lady alowed it to be used to stop the War.
I don't remember what Shekelor's deal was.
And
The ancient wizard was Rowan Darkwood, sent back in time (way back) without his memory by the Lady.
...
Faction War's not my favorite module. If you read a list of things not to do as a DM, you'd find most of them built in to that module.