The Oracle is a character from Strife. It appears to the player as a robed human wearing a blue mask. It uses The Order's minions as guards and a Spectre can be seen floating in a hole at the ceiling of the Oracle's room.
When the player shoots it, the mask and robe fall off revealing a skull on a non-human body that proceeds to fall apart. Whether it was alive before the player shot it or whether it was simply a dummy for the afore mentioned Spectre to speak through without arousing suspicion is undisclosed.
Once the Oracle is killed, the Spectre comes through the hole to attack the player.
The Oracle is also a source of information. After the Programmer is destroyed in the Order's castle, Macil wants the player to find four other sigil pieces, and tells the player to ask the Oracle for information about the pieces' whereabouts. The Oracle sends the player to kill the Bishop. After that, it claims that Macil is one of the enemy. It is possible to choose at this point whether to kill Macil and listen to the Oracle, or to go with Macil and be convinced that the Oracle is the enemy. The path taken here affects the "good" ending of Strife.
If Macil is killed first, the worse of the two good endings is presented. It is not possible to travel to the Conversion Chapel that turns humans to Acolytes, as the Oracle will send the player to the Loremaster. After killing the Loremaster, it is necessary to kill the Oracle to get the last Sigil piece.
If the Oracle is killed first, then the better of the two endings is presented, as Macil sends the player to a factory where a cure for the virus in the story is found, and Blackbird's true appearance will be revealed.