Ravel Mod/Hole of Merez

Hole of Merez is a magic weapon that drops from Wall of Flesh with 10% chance. It summons a fire hole that pulls nearby enemies, dealing damage and inflicting On Fire! debuff for 5 seconds to them. After about 2 seconds, a miniature Wall of Flesh appears dealing massive damage and disappears. Its best modifier is Mythical.

Trivia
Hole of Merez is a reference to the situation from Merez's (polish youtuber) modded terraria gameplay where he got stuck in a hole while fighting Wall of Flesh and died. After this it became meme beyond his fans.