The Crusader is one of 6 playable classes in Diablo Immortal.
"Faith is a Crusader’s weapon. Striking with cruel flails and clad in impenetrable armor, Crusaders wander the land, vanquishing evil wherever they go and dominating the battlefield through sheer purpose."
A typical support/healing archetype, the Crusader can also pack a punch and take enemies head on, destroying them with Holy Light.
It is not know at this time what abilities Crusaders will have in Diablo Immortal.