This card is the best thing ever for almost any archetype or strategy that features a Level 6 or higher Spellcaster, plus it also super synergizes with any Spell or Trap cards that can gain extra advantage when sent or from the GY
Having these creatures die and not having anything in the graveyard to reanimate hurts quite a bit, so in the early game, it is sometimes a good idea to try to discard a cheap creature like Evolved Sleeper or Faerie Vandal to Tainted Indulgence or Evangel of Synthesis so we'll have something in our graveyard to reanimate once our Puppeteers and Anointers start hitting the battlefield
Sky Strikers
I believe that this card is the most useful because it can demonstrate "Even if you add 1100 to your girlfriend's ATK of 1100, it's still water." Her ATK line is 2400, so she can't exceed it, even if it's against high-level monsters
I learned about card thickness, soft touch vs velvet touch, foil printing, QR codes
I absolutely love the Korean 1st edition Zard