These servants have been corrupted by the black mud that flows through from the mansion of souls, each one of them is contracted to drix and they seem to mainly play a more behind the scenes role.

Caster of the black mud

Personality: unknown
Hidden abilities: servant of the black mud (takes half damage from magic and has access to the black mud and all its abilities)
Old blood
Weapons; none
Class: caster
True name: unknown
Characteristics; unknown
Rank: EX
grand Magic: ???
Rank explanation: not enough data

Assassin of the black mud

Personality: unknown
Class: assassin
Hidden abilities: servant of the black mud
One with many faces (she can make clones of herself that all look different and have different talents)
True name: unknown
Grand magic: ???
Characteristics: unknown
Rank: EX
rank explanation; not enough data

Warrior of the black mud

Personality: unknown
Hidden abilities: servant of the black mud
Unifier of Japan (deals double damage to all Japanese servants, all Japanese servants fighting alongside him gave double the power, double power while in Japan, master ship of all Japanese weaponry)
Grand magic: ???
Rank: EX
class: warrior
True name: unknown
Characteristics: Japanese, all other characteristics unknown
Rank explanation: none enough information

Archer of the black mud

Personality: unknown
Hidden abilities: servant of the black mud
Merry women (she can call a series of assistants known as the merry men, double damage to all other British servants)
Grand magic: king killing shot
True name: maid Marian
Characteristics: British but all others are unknown
Class: archer
Rank: EX
rank explanation: maid Marian has some great hidden abilities, servant of the black mud is already an amazing hidden ability and merry women just provided her with some additional support to keep her enemies at a distance and gives her a nice advantage over other British servants such as Robin Hood on top of all of this her grand magic deals quadruple damage to all royalty and even when she's not attacking royalty it still packs quite the punch

Berserker of the black mud

Personality: unknown
Class: berserker
True name: unknown
Rank: EX
Hidden abilities: servant of the black mud
Royal authority (only royalty can deal grand magic damage to him and all other servants deal half damage to him, he deals double damage to all non-royal servants)
Grand magic: ???
Characteristics: royal but all others are unknown
Rank explanation: none enough information

Alterer of the black mud

Personality: unknown
Class: alterer
True name: Baba Yaga (alter)
Grand magic: ???
Hidden abilities: servant of the black mud
Imperfect alteration (her alteration into an alter wasn't completed so she become a alterer class which shouldn't technically be possible because of this her stats can change at random and she can access the powers of her traditional self and her alter self)
Rank: EX
Characteristics: alter, Russian, fictional, all others unknown
Rank explanation: not enough information

Reverser of the black mud

Personality: -cannot be revealed-
True name: -cannot be revealed-
Hidden abilities: -cannot be revealed-
Grand magic: -cannot be revealed-
Hidden abilities: servant of the black mud
-Cannot be revealed-
Rank: EX
Characteristics: -cannot be revealed-
Rank explanation: -cannot be revealed-

Ruler of the black mud

Personality: unknown
Hidden abilities: servant of the black mud
Ruler of all things (she can deal double damage against all servants except for a select few (ex: Queen of Sheba, schenzarde), she can access the powers of all servants that she fought against but if the skill has a rank it reduces to its lowest rank, she cannot be altered, she is not affected by debuffs)
Rank: EX+
True name: the amalgamation
Grand magic: ruler of all things (amalgamation)
Characteristics: none
Rank explanation; the amalgamation is a servant made up of a bunch of different legends that were shaken around and dumped out and her kit reflects that, her black mud ability is good and that's no secret but her second skill is amazing, it affects all but a select few servants and makes her immune to all kinds of things that would normally be the end of a servant like her on top of all of this she can also access almost all of the skills that servants get. The downside to all this power though is that she has very weak defenses and her grand magic does pretty pitiful damage and has no bonus effects.

Foreigner of the black mud
True name: H.P. lovecraft
-no other information available-