They werent designed as tournament-legal cards, but a representation of their anime appearance for fans to recreate scenes from the anime through their own memories of their seemingly-infinite power and endless abilities
On a failed spin, Time Wizard and the Duelists own Monsters are destroyed, and the Duelist loses Life Points equal to half of their combined Attack Points
After their first duel, and between each duel from then on, each player can choose to replace cards in their Main Deck and/or Extra Deck with cards from their Side Deck
The prize card is printed in stainless steel, hence making it a non-Game card
C Common Megarock Dragon X EARTH Level 7 [ RockEffect ] ATK
Both Scythe (with first effect, of course) and Immortality feel a little too strong: I would restrict one to once per turn and the other to twice per turn, depending on your thoughts over which should be nerfed more