Crazy take: Arborgias’ Legendary Ultra-Evolution.
Name: Arboregis
Rarity: 6★
Element: Earth
Cost: 13 (16 with SS)
Statline: full defence
Speed: 25%
MOVESET: ACTIVE SKILLS
Ground Eater: deals medium damage, and extra damage to same-element monsters. Reduces seconds by 100 if it successfully kills (160 TU).
LINK Deathstroke (130 TU, 2 uses).
LINK Godslayer: deals lethal damage to monsters who have 6 or more stars (160 TU).
Double Bloodthirst (160TU).
SECRET SKILL - Death Conversion: immediately kills the chosen enemy and summons a Geowolf in his place. Can only be used after 150 sec from its first turn. (70 TU)
MOVESET: PASSIVE SKILLS
Anti-Death Shield: this monster is immune to Death Sentence. If this monster is targeted by a passive skill like Death Revenge, or a skill like Deathstroke or Sudden Death, its seconds are increased by 150 instead.
Unmovable
EDIT: forgot to mention this monster must NOT appear in any Island Challenge
EDIT 2: various suggested changes