The Winged Fire enemy type plays a loud metallic clang noise when they die, which is fairly similar to the sound that plays when a unique item drops. They also glow with a bright, vertical orange/golden beam of light while using one of their skills.
Combined, these two effects lead to frequent “Ooh a unique! Oh never mind…” moments while fighting them. Constant disappointment is a feeling that should be avoided in these types of games.
I suggest reworking their death sound and visual effects to be less similar to drop effects.