When an opponent casts a spell, if Veiled Apparition is an enchantment, Veiled Apparition becomes a 3/3 Illusion creature with flying and "At the beginning of your upkeep, sacrifice Veiled Apparition unless you pay ."
When one of your opponents successfully casts a spell, if Veiled Apparition is an enchantment, Veiled Apparition becomes a 3/3 creature with flying and "During your upkeep, pay or sacrifice Veiled Apparition" and that counts as an Illusion.
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