Lystêrn

Lunalight Teal Ocelot
DARK
Beast-Warrior/Xyz/Effect
Rank 4 - 1800/2000

2 Level 4 "Lunalight" monsters
While you control a face-up "Lunalight" Fusion monster, you can activate this card's effect without detaching a Xyz Material. Once per turn, you can detach 1 Xyz Material to target 1 "Lunalight" monster among your banished cards, Special Summon it with its effects negated.
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Stretch "Number" monsters beyond 107.(Bonus point if you make that card archetype related.)

False God's Vessel

DARK
Psychic/Negative/Effect
Level 4 - 1100/2100

(This card's Level can be treated as Level -4.)
If this card is Normal or Special Summoned: Send 1 card from your hand to GY. During your turn, except the turn this card is sent to GY: Banish this card from your GY; then Special Summon 1 Negative monster from your GY. You can use this effect of "False God's Vessel" once per turn.
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Negative form of existing card.

Infinite Ignition Riverstorm

EARTH Machine Xyz Effect Monster
RK5 2500/500
Materials: 2 Level 5 monsters
You can only use the 1st and 3rd effects of this card’s name each once per turn.
(1) You can detach 1 Xyz Material from this card; either add 1 EARTH Machine monster from your Deck to your hand, or send 1 EARTH Machine monster from your Deck to the GY.
(2) When this card destroys an opponent’s monster by battle: You can attach that monster to this card as Xyz Material.
(3) If this card is in the GY: You can Tribute 1 Machine Link Monster; Special Summon this card in Defense Position.

Wind-Up Knightmare
WIND
Fiend/Link/Effect
Link 2 - ATK 1500
S/SW

2 Machine monsters, including at least 1 "Knightmare" monster
If this card is Link Summoned: Target 1 monster you control that has a Level; increase that monster's Level by 2, and if this card is co-linked, draw 1 card. You can use this effect of "Wind-Up Knightmare" once per turn.
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Shaddoll + Fluffal (Or Frightfur)