Shadowcaster

Shadowcasters were spellcasters who had forged a direct link with the Plane of Shadow.

Most often found working for the churches of deities who grant access to the darkness domain, shadowcasters tended to be solitary individuals who faced persecution from paladins and good-aligned clerics regardless of their actual actions and intentions, due to a belief that anyone so closely linked to the plane of shadow must be inherently evil.

True, the shadow plane was full of evil entities but the plane itself was only mildly evil-aligned and anyone with a disciplined enough mind could master the bizarre power available from it. Many also thought shadowcasters were tied to Shars Shadow Weave but this was not the case. Due to the direct link a shadowcaster had with the plane itself, its powers could just as easily be accessed with the Weave.

Abilities
As they grew more powerful, they unlocked mysteries - thought processes and powers known to few outside the plane itself due to their alien nature - much like a warlock would learn invocations. Unlike a warlock however, the further a shadowcaster progressed, the easier they found their mysteries to manipulate. Shadowcasters also gained the ability to see in the dark (or see better in darkness if they already could see in the dark) and the link they formed with the plane also sustained their bodies with dark energy, lessening the need to eat, drink or rest and negating the effects of poisons and diseases.