In Zelda: Tears of the Kingdom, Deep Firefly are critters that can't be consumed raw but are typically used in elixirs. Most insects or critters offer various status effects or boost the duration of a status effect when added to crafting an elixir.

The Deep Firefly, in particular, offers a Glow status effect and contributes 00:30 base time duration of the effect in the crafted elixir.

When fused with a weapon it gives the following Attack Power Bonus:

    It can be used as an ingredient to cook the following meals:

    It can be used as an material to upgrade the following armor: