gacha spook
When you roll for a character in a gacha, but you're "spooked" by another character appearing instead. You can get spooked for negative or positive reasons.
Sometimes it's based on the character's silhouette, sometimes it's based on gameplay mechanics which hint at the character to come, like their class or rarity being shown off first, or in construction-based gachas the time given after you begin producing a new character, etc.
Examples
