Soul layers mechanic creates multiple levels(planes) of afterlife in game, depicted as ghosts of previous level. Example:
Level0: Physical, players can only see physical and interact with physical.
Level1: Dead players, can see both Level0 and level1, can interact within level1.
Level2: dead players from level1, can see Levels 2-0 can interact with Level2 content.
Level3:dead players from level2, can see Levels3-0 and can interact only with level3, when they die they restart in town as level0 live players.