Gargauth

Gargauth (pronounced GAR-goth ), or The Lord Who Watches, is the lawful evil demigod of betrayal, cruelty, political corruption and powerbrokers. He embodies the inevitable decay and corruption that accompanies all self-serving, greedy, and power-hungry leaders and groups. Gargauth holds to the letter of any agreement, not the spirit, and relishes betraying anyone with whom he forges a pact by twisting the contract to serve his own ends.

Worshipers
The church of Gargauth is a secretive faith, although there are some significant exceptions. Clerics work to increase their personal power, the power of the church, and by extension, the power of Gargauth; they are expected to be Gargauth's eyes and ears throughout Faerûn. They are to entice and corrupt powerful individuals and leaders in communities throughout Faerûn and bind them into strict contracts favorable to Gargauth's goals. They seek to seize positions of power whenever possible and integrate their positions into the secretive hierarchy of the faith. Gargauth has directed his followers to undermine other evil faiths and steal their worshipers rather than waste energy in conflicts with good deities. Clerics of Gargauth pray for their spells at dusk, when night first begins to corrupt the day. Gargauth's clergy mark all agreements with signed contracts consecrated in the name of the Lord Who Watches. Many clerics multi-class as divine disciples or sorcerers.

Holy Days
This occurs each Midwinter night. This horrific ceremony, believed to involve many gruesome sacrifices, heralds the imminent time when Gargauth shall seize Faerûn as his unholy kingdom and transport it to Baator to form the Tenth Pit of Hell.
 * The Unveiling :

This is celebrated on the eve of the Feast of the Moon. It is a personal ritual in which each cleric renews his eternal contract with Gargauth, trading absolute fealty for increased power. This unholy ritual is believed to involve personal sacrifices of money, magic, and hoarded knowledge and the casting of many horrific spells.
 * The Binding :

Relationships
Gargauth is opposed to evil deities such as Cyric and Shar. He poses a particular threat to Siamorphe, given his interest in corrupting those who she holds up as shining paragons of virtue.

Gargauth sometimes employs a powerful blue dragon named Rathguul as a steed.

History
Gargauth is a former arch-devil whose foul nature was too much even for others of his ilk. Exiled from the Nine Hells, Gargauth took to wandering the planes, returning time and again to Toril.

Dogma
"Life is all based about the accumulation of power. Civilization is a thin veneer over the base desires that make up the core of every living being. Those who wish to survive and prosper must recognize this truth and concentrate all their resources on the pursuit of power. High moral principles are complete hypocrisy. All beings act in their own self-interest at all times; some just prefer to cloak their actions in sanctimonious philosophies. To achieve power one should use one's charms and honeyed words or a barded and bloody dagger as appropriate for the situation. When in doubt, the ruthless exercise of power is the safest route to the further accumulation of power and the maintenance of one's position. It is more important to rule than to sit on the throne; often the being behind the king has the true power. All beings are regimented in a strict hierarchy governed by the politics of power. Those who try to avoid the rules of the game are destined for powerlessness, to be cast in the dust of history and ground beneath the heels of the powerful, but be prepared to twist any contract or stricture so as to maximize the benefit you receive."