Created by: YGO Mod (20517634)
Created On: 06/23/2025
Nemesis of the Underground Terror
Main: 20 Extra: 6








Subterror Fiendess
ATK:
800
DEF:
500
When your opponent activates a card or effect (Quick Effect): You can send this card from your hand or field to the GY, then target 1 "Subterror" monster you control; negate the activation, then change the targeted monster to face-down Defense Position. You can target 1 face-up monster you control; change it to face-down Defense Position, and if you do, Special Summon 1 "Subterror" monster from your hand or GY, in face-up or face-down Defense Position. You can only use each effect of "Subterror Fiendess" once per turn.








Subterror Fiendess
ATK:
800
DEF:
500
When your opponent activates a card or effect (Quick Effect): You can send this card from your hand or field to the GY, then target 1 "Subterror" monster you control; negate the activation, then change the targeted monster to face-down Defense Position. You can target 1 face-up monster you control; change it to face-down Defense Position, and if you do, Special Summon 1 "Subterror" monster from your hand or GY, in face-up or face-down Defense Position. You can only use each effect of "Subterror Fiendess" once per turn.








Subterror Fiendess
ATK:
800
DEF:
500
When your opponent activates a card or effect (Quick Effect): You can send this card from your hand or field to the GY, then target 1 "Subterror" monster you control; negate the activation, then change the targeted monster to face-down Defense Position. You can target 1 face-up monster you control; change it to face-down Defense Position, and if you do, Special Summon 1 "Subterror" monster from your hand or GY, in face-up or face-down Defense Position. You can only use each effect of "Subterror Fiendess" once per turn.








Subterror Behemoth Ultramafus
ATK:
3000
DEF:
1800
FLIP: You can change all other face-up monsters on the field to face-down Defense Position. You can only use this effect of "Subterror Behemoth Ultramafus" once per turn. When a face-up monster you control is flipped face-down, if you control no face-up monsters: You can Special Summon this card from your hand in Defense Position. Once per turn: You can change this card to face-down Defense Position.








Subterror Behemoth Umastryx
ATK:
2000
DEF:
2700
FLIP: You can target 1 monster your opponent controls; banish it. You can only use this effect of "Subterror Behemoth Umastryx" once per turn. When a face-up monster you control is flipped face-down, if you control no face-up monsters: You can Special Summon this card from your hand in Defense Position. Once per turn: You can change this card to face-down Defense Position.








Subterror Guru
ATK:
1600
DEF:
1800
FLIP: You can add 1 "Subterror" card from your Deck to your hand, except "Subterror Guru". You can target 1 other face-up monster on the field; change that monster, also this card, to face-down Defense Position. This is a Quick Effect if you control another "Subterror" card. You can only use each effect of "Subterror Guru" once per turn.








Subterror Guru
ATK:
1600
DEF:
1800
FLIP: You can add 1 "Subterror" card from your Deck to your hand, except "Subterror Guru". You can target 1 other face-up monster on the field; change that monster, also this card, to face-down Defense Position. This is a Quick Effect if you control another "Subterror" card. You can only use each effect of "Subterror Guru" once per turn.








Subterror Guru
ATK:
1600
DEF:
1800
FLIP: You can add 1 "Subterror" card from your Deck to your hand, except "Subterror Guru". You can target 1 other face-up monster on the field; change that monster, also this card, to face-down Defense Position. This is a Quick Effect if you control another "Subterror" card. You can only use each effect of "Subterror Guru" once per turn.








Forbidden Droplet
Send any number of other cards from your hand and/or field to the GY; choose that many Effect Monsters your opponent controls, and until the end of this turn, their ATK is halved, also their effects are negated. In response to this card's activation, your opponent cannot activate cards, or the effects of cards, with the same original type (Monster/Spell/Trap) as the cards sent to the GY to activate this card. You can only activate 1 "Forbidden Droplet" per turn.








Forbidden Droplet
Send any number of other cards from your hand and/or field to the GY; choose that many Effect Monsters your opponent controls, and until the end of this turn, their ATK is halved, also their effects are negated. In response to this card's activation, your opponent cannot activate cards, or the effects of cards, with the same original type (Monster/Spell/Trap) as the cards sent to the GY to activate this card. You can only activate 1 "Forbidden Droplet" per turn.








The Hidden City
When this card is activated: You can add 1 "Subterror" monster from your Deck to your hand. Once per turn: You can change 1 face-down Defense Position "Subterror" monster you control to face-up Attack or Defense Position. Once per turn, when an opponent's monster declares an attack: You can change 1 face-down Defense Position "Subterror" monster you control to face-up Attack or Defense Position, then you can negate the attack. You can only activate 1 "The Hidden City" per turn.








The Hidden City
When this card is activated: You can add 1 "Subterror" monster from your Deck to your hand. Once per turn: You can change 1 face-down Defense Position "Subterror" monster you control to face-up Attack or Defense Position. Once per turn, when an opponent's monster declares an attack: You can change 1 face-down Defense Position "Subterror" monster you control to face-up Attack or Defense Position, then you can negate the attack. You can only activate 1 "The Hidden City" per turn.








The Hidden City
When this card is activated: You can add 1 "Subterror" monster from your Deck to your hand. Once per turn: You can change 1 face-down Defense Position "Subterror" monster you control to face-up Attack or Defense Position. Once per turn, when an opponent's monster declares an attack: You can change 1 face-down Defense Position "Subterror" monster you control to face-up Attack or Defense Position, then you can negate the attack. You can only activate 1 "The Hidden City" per turn.








Subterror Final Battle
Activate 1 of these effects, also, after that, Set this card face-down instead of sending it to the GY. ● Change 1 Set "Subterror" monster on the field to face-up Attack or Defense Position. ● Change 1 face-up "Subterror" monster on the field to face-down Defense Position. ● ATK/DEF of 1 "Subterror" monster on the field become equal to its combined original ATK/DEF until the end of this turn. ● This turn, activated effects of "Subterror" cards cannot be negated.








Subterror Final Battle
Activate 1 of these effects, also, after that, Set this card face-down instead of sending it to the GY. ● Change 1 Set "Subterror" monster on the field to face-up Attack or Defense Position. ● Change 1 face-up "Subterror" monster on the field to face-down Defense Position. ● ATK/DEF of 1 "Subterror" monster on the field become equal to its combined original ATK/DEF until the end of this turn. ● This turn, activated effects of "Subterror" cards cannot be negated.








Subterror Final Battle
Activate 1 of these effects, also, after that, Set this card face-down instead of sending it to the GY. ● Change 1 Set "Subterror" monster on the field to face-up Attack or Defense Position. ● Change 1 face-up "Subterror" monster on the field to face-down Defense Position. ● ATK/DEF of 1 "Subterror" monster on the field become equal to its combined original ATK/DEF until the end of this turn. ● This turn, activated effects of "Subterror" cards cannot be negated.







Knightmare Phoenix
ATK:
1900
LINK-2
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Right
2 monsters with different names If this card is Link Summoned: You can discard 1 card, then target 1 Spell/Trap your opponent controls; destroy it, then, if this card was co-linked when this effect was activated, you can draw 1 card. You can only use this effect of "Knightmare Phoenix" once per turn. Co-linked monsters you control cannot be destroyed by battle.







Knightmare Unicorn
ATK:
2200
LINK-3
Link Arrow:
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Bottom
2+ monsters with different names If this card is Link Summoned: You can discard 1 card, then target 1 card on the field; shuffle it into the Deck, then, if this card was co-linked when this effect was activated, you can draw 1 card. You can only use this effect of "Knightmare Unicorn" once per turn. While any co-linked "Knightmare" monsters are on the field, for your normal draw in your Draw Phase, draw 1 card for each different card name among those co-linked "Knightmare" monsters, instead of drawing just 1 card.







Underworld Goddess of the Closed World
ATK:
3000
LINK-5
Link Arrow:
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Top-Right
Right
Bottom
Bottom-Right
4+ Effect Monsters You can also use 1 monster your opponent controls as material to Link Summon this card. If this card is Link Summoned: You can negate the effects of all face-up monsters your opponent currently controls. This Link Summoned card is unaffected by your opponent's activated effects, unless they target this card. Once per turn, when your opponent activates a card or effect that Special Summons a monster(s) from the GY (Quick Effect): You can negate the activation.








Abyss Dweller
ATK:
1700
DEF:
1400
2 Level 4 monsters While this card has a material attached that was originally WATER, all WATER monsters you control gain 500 ATK. Once per turn (Quick Effect): You can detach 1 material from this card; your opponent cannot activate any card effects in their GY this turn.








Number 70: Malevolent Sin
ATK:
2400
DEF:
1200
2 Level 4 monsters Once per turn: You can detach 1 Xyz Material from this card, then target 1 monster your opponent controls; banish it until your opponent's next Standby Phase. At the end of the Damage Step, if this card attacked: You can make this card gain 300 ATK, and if you do, increase its Rank by 3.