Shadowy Figure

The Shadowy Figure is a person that Gorion's Ward encounters several times during the events of Baldur's Gate: Siege of Dragonspear. They seem to be testing Gorion's Ward, but they refuse to give any indication of what their plans are.

Appearances
The Shadowy Figure appears at several points during Siege of Dragonspear, some mandatory, and some optional. The most direct confrontation is in the Underground River.

Spoiler Content
At the end of Siege of Dragonspear, the Shadowy Figure arranges for the murder of Skie Silvershield and frames Gorion's Ward for the deed. This leads to their expulsion from Baldur's Gate, setting up their capture and imprisonment for the beginning of Baldur's Gate II: Shadows of Amn.

It is very obvious that the Shadowy Figure is, in fact, Jon Irenicus, and neither his voice nor his actions really conceal this fact from players.