My takes on Mortifying Mansion theme (ft. Metaphyspirit)

Mortifying Mansion
Field Spell
Zombie and Fiend monsters you control cannot be destroyed by battle or your opponent's card effects. If this card would be sent to the GY or banished by an opponent's card; you can send 1 "Sporadic Specter" or "Horrifying Haunt" from your hand or Deck to the GY, instead. You can only use this effect of "Mortifying Mansion" twice per turn.

Tome of Terror
Continuous Spell
When this card is activated: You can activate 1 "Mortifying Mansion" from your Deck or GY. While "Mortifying Mansion" is banished, in your Field Zone, or in your GY, Zombie and Fiend monsters you control gain 1000 ATK/DEF. You can only activate 1 "Tome of Terror" per turn.

Sporadic Specter
Level: 4 DARK
Zombie/Effect
If this card is Normal or Special Summoned: You can send 1 card from your hand to the GY; add 1 Spell/Trap that mentions "Mortifying Mansion" from your Deck to your hand. You can only use this effect of "Sporadic Specter" once per turn.
ATK: 1550 DEF: 850

Horrifying Haunt
Level: 4 DARK
Fiend/Effect
If this card is Normal or Special Summoned: You can send 1 card from your hand to the GY; Special Summon 1 monster that mentions "Mortifying Mansion" from your Deck, except "Horrifying Haunt". You can only use this effect of "Horrifying Haunt" once per turn.
ATK: 1550 DEF: 850

Malicious Mannequin
Level: 4 DARK
Fiend/Effect
If this card is sent from the hand to the GY: Special Summon it. If this card is Normal or Special Summoned: You can target 1 monster that mentions "Mortifying Mansion" in your GY, except "Malicious Mannequin"; add it to your hand. You can only use this effect of "Malicious Mannequin" once per turn.
ATK: 1550 DEF: 850

Prankster Poltergeist
Level: 4 DARK
Zombie/Effect
If you control "Mortifying Mansion", you can Special Summon this card (from your hand). You can only Special Summon "Prankster Poltergeist" once per turn this way. If this card is Normal or Special Summoned: You can target 1 monster that mentions "Mortifying Mansion" in your GY, except "Prankster Poltergeist"; Special Summon that target. You can only use this effect of "Malicious Mannequin" once per turn.
ATK: 1550 DEF: 850

Mortifying Malevolent Mansion
Level: 10 DARK
Zombie/Fusion/Effect
"Sporadic Specter" + "Horrifying Haunt"
Must first be Special Summoned (from your Extra Deck) by banishing the above cards and 1 "Mortifying Mansion" you control and/or from your GY. If this card is Special Summoned, or a monster(s) is Special Summoned to your opponent's field: You can destroy Spells/Traps your opponent controls, up to the number of your banished cards with different names, that are "Mortifying Mansion" and/or cards that mention it. You can only use this effect of "Mortifying Malevolent Mansion" once per turn.
ATK: 3250 DEF: 2950

Harrowing Haunted House
Level: 10 DARK
Fiend/Fusion/Effect
"Malicious Mannequin" + "Prankster Poltergeist"
Must first be Special Summoned (from your Extra Deck) by banishing the above cards and 1 "Mortifying Mansion" you control and/or from your GY. If this card is Special Summoned, or a monster(s) is Special Summoned to your opponent's field: You can banish cards from your opponent's GY, up to the number of your banished cards with different names, that are "Mortifying Mansion" and/or cards that mention it. You can only use this effect of "Harrowing Haunted House" once per turn.
ATK: 3250 DEF: 2950

Ravenous Rampant Residence
Level: 11 DARK
Zombie/Fusion/Effect
4 monsters with 1550 ATK and 850 DEF with different names (2 Zombie, 2 Fiend)
Must first be Special Summoned (from your Extra Deck) by banishing the above cards and 1 "Mortifying Mansion" you control and/or from your GY. If this card is Special Summoned, or a monster(s) is Special Summoned to your opponent's field: You can banish as many cards on the field as possible (other than cards that are "Mortifying Mansion" or mention them), and if you do, inflict 600 damage to your opponent for each card banished. You can only use this effect of "Ravenous Rampant Residence" once per turn.
ATK: 4250 DEF: 3950