Extracts from "The Book of Marvels.
Now, we must consider the immortals, and distinguish between those who know bliss and those who are damned. Pacts with the demon do not guarantee everlasting life in this world. For the lowly henchmen of Satan (or any other name you may give him), mere invocation or combat is enough.
But remember this: there is a time of remission after the first death which rips away earthly appearances, and the second death, which is true and final death, and which leads the damned soul to Hell. The time we call the "Latent Period" is when the cursed one is sent to the time of his damnation and becomes vulnerable once more.
A weapon forged during the. pact is enough to send them back to the void. For wizards, it is not so easy. The pact must be eradicated by destruction and conjuring...
Whatever the price. That is what the virtuous must pay to remove the curse of an eternal life devoted to sin.