Just as every Wraith is unique, so is every Shadow. Every soul must beat its own, individual path to Hell, or whatever nightmare lurks beyond the Barrier.
 
That said, there are some general "types" of Shadow, each of which operates within certain parameters. These types correspond to the recognized Virtues and Vices of an individual's Morality, and act as a deranged outgrowth of one of them. This is most often the side of the personality that the Wraith did not appreciate in life, but it can also be a dark reflection of the preferred side of her personality as well.
 
Death is nothing if not ironic...
 

The Heart's Thorn:
 
Each Shadow Type has a particular Thorn that is unique to that Type, and these special powers are referred to as Heart's Thorns.

Unlike other Thorns, they don't cost Tainted Essence to activate, and won't give the Shadow power over the Wraith. They instead give the Shadow a chance to get Tainted Essence directly back, even if not in Shadowstate, by offering dice to their Wraiths.

Once the Wraith's Angst is powerful enough for Thorns' physical blemishes to manifest outside of Shadowstate, the Heart's Thorn is most likely to show up first. It's not unknown for another to jump to the head of that line, though. It all depends on the Shadow, and how it views itself and the Wraith it's been shackled to. 
 
Heart's Thorns cannot be purchased or gained by Shadows - they come with the Type, and are not interchangeable.

Certain Considerations

A Heart's Thorn allows the Shadow to offer extra dice in certain situations, which must correspond with the goals of the Shadow's Type. One die may be offered for each dot of Angst the Shadow has, but Shadows don't have to offer over all the dice they could. How many dice are actually handed over is for the Wraith and her Shadow to discuss between them, but once the decision is made and agreed to, these tainted dice are duly given so long as the Wraith actually follows through.
 
Should the Wraith follow through, then the Wraith can use these dice in her next roll to do something they've agreed upon. All the dice the Shadow offered must be used at this time. And the Shadow gains a dot of Tainted Essence for each Tainted Die that comes up '10' - including any '10's scored on the re-roll - as this result affirms the Shadow's self-esteem. {It's recommended that the Tainted Dice be of a different color than the rest of the dice in the roll, just to make keeping track easier.}

Shared Convictions

Heart's Thorns do offer a shared advantage, should the Wraith choose to invoke them in Shadowstate. These powers tend to affect other Wraiths in the same way the Shadow would like to affect the Wraith, herself, or else they cause other Wraiths to behave the way the Shadow would prefer them to act towards the Wraith.

When the shared aspect of the Heart's Thorn is used, the Shadow gains Tainted Essence, just as though it were a normal Thorn. She makes the appropriate roll, as listed in the rules for the Heart's Thorns, and the Shadow gets a dot of Tainted Essence whether the power works or not. These shared powers may last for a turn, a Scene, or another passage of time, depending on the Thorn.

The Best Defense

Heart's Thorns also offer another advantage to the Wraith - that of being protected against her own tricks.

Should another Wraith with the same Shadow Type attempt to use her Heart's Thorn on the Wraith, she will detect it instantly, and may elect to go into Shadowstate to try and block it. And unlike most Shadowstates, the Wraith may enter it without needing to ask her Shadow's permission, though this gives the Shadow an automatic dot of Tainted Essence for the violation.

Once in the Shadowstate, the Wraith may roll for the Heart's Thorn, which gives the Shadow a dot of Tainted Essence as normal. Each success takes away one of the other Wraith's successes to affect her. In fact, should the Wraith's successes exceed the other Wraith's, then the effect is broken for all who would have been affected.