Firebane (5e Equipment)
From D&D Wiki
A sword made of obsidian from forge mountain, infused with power from the hottest layer of the Abyss made by the First Archmage of the Arcadian mage guild as a counter measure against energy. The blade absorbs dangerous magical energy like fire, lightning, radiance, and even the power of a Dark Beast.
Fire. This blade is surrounded by fire that emits a dim light level around it, though the flame is hot. This sword deals an addition 2d6 fire damage.
Energy Absorption. When the blade comes in contact with energy, it will absorb it, causing the fire to burn hotter. Each time this happens, firebane deals 1d6 more fire damage for 2 minutes (this stacks). Energy is considered radiance, fire, lightning. Stacks are gained through either of the following methods:
Even though the entire plot revolves around slaying the Greater Dark Beast, I like to put in scenes like this to highlight just how strong these creatures are supposed to be. When a player attacks with firebane on a Greater Dark Beast have the following scene play out. “The sword when stabbing the beast, gets lodged into it. The sword in your hands gets hotter and hotter until you are forced to let go. The beast roars in pain as the blade turns a bright blue. The blade shakes violently, it looks like it can’t take these levels of heat and might explode. You should run for it.” In 5 turns the blade will explode in a blue wave of fire. Anyone in a hundred foot radius of the blast (including the beast) will take 500 + 5d100 fire damage and a crater will be left behind, with a crisp form of the Dark Beast struggling to get back up, fall and stop moving. That is more than enough to kill almost any Greater Dark Beast except for The Greater Fire (takes no damage) and the Greater Dark Beast of Earth (remove half of the beasts maximum health to show this).