Regulus
Level 4 LIGHT/Beast Effect1700 ATK / 1000 DEF
Once per turn, you can select 1 Field Spell Card in your Graveyard. Return it to the Deck.
Regulus the Fairy Beast
Level 4 LIGHT/Beast Effect1700 ATK / 1000 DEF
If this card is Normal or Special Summoned: You can add 1 Spell/Trap that mentions "Ancient Fairy Dragon" from your Deck to your hand. During your Main Phase: You can Special Summon 1 Level 4 or lower LIGHT monster (Beast, Plant, or Fairy) from your hand in Defense Position. You can banish this card from your GY, then target 1 Field Spell in your GY; place it on the bottom of the Deck, then draw 1 card. You can only use each effect of "Regulus the Fairy Beast" once per turn.
Regulus, the Prince of Endymion
Level 4 LIGHT/Spellcaster Effect1700 ATK / 1300 DEF
The first time this card would be destroyed by battle each turn, it is not destroyed. You can only use each of the following effects of "Regulus, the Prince of Endymion" once per turn. If this card is in your hand: You can reveal 1 other Spellcaster monster in your hand; you lose LP equal to the revealed monster's Level x 300, and if you do, Special Summon this card. If this card is Special Summoned: You can add 1 Spell that mentions "Regulus, the Prince of Endymion" from your Deck to your hand.
Regulus' Arrow
Quick-Play SpellIf you control "Regulus, the Prince of Endymion": Activate 1 of these effects;
● Destroy 1 monster your opponent controls that battled this turn.
● When a Normal or Quick-Play Spell Card is activated: Negate that effect.
During your Main Phase: You can banish this card from your GY, then target 1 "Regulus, the Prince of Endymion" or 1 monster that mentions it in your GY; Special Summon it. You can only use each effect of "Regulus' Arrow" once per turn.
Therion "King" Regulus 20
Level 8 EARTH/Machine Effect2800 ATK / 1600 DEF
You can only use each of the following effects of "Therion "King" Regulus" once per turn.
● You can target 1 "Therion" monster or 1 Machine monster in your GY; Special Summon this card from your hand, and if you do, equip that monster to this card.
● When your opponent activates a card or effect (Quick Effect): You can send 1 "Therion" Monster Card from your hand or face-up field to the GY; negate that effect.
A "Therion" monster equipped with this card gains 700 ATK, also it can activate the 2nd effect listed above as if it were "Therion "King" Regulus".