[Shadow] Artifact - Zenith Catalyst

Inside this cube is a divine relic of the sun goddess Zentha, originally used for good but now as an instrument of death. According to Daybroken doctrine, the ultimate champion of Zentha is capable of withstanding the full force of the Blighted Sun. Based solely on this prophecy, fanatical Daybroken sects endeavor to create a device that can identify the champion — at the cost of thousands of lives.

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ZENITH CATALYST
Wondrous item, artifact

A magical sundial atop this cube tells the current time.

Stored within this pulse bomb is the concentrated poison radiance of the Blighted Sun, and a fragment of the divinity that represents it. You can use an action to activate this bomb. The bomb emits a low hum until it detonates at next noon, releasing a burst of radiant energy that travels through nearly all materials in a 1,000-foot radius sphere around the bomb. Only a layer of lead with a thickness of 5 feet or more provides total cover against the bomb.

Each creature in the area must make a DC 20 Dexterity saving throw, taking 6d10 radiant damage and 6d10 poison damage on a failed save, or half as much on a successful one. A creature that takes four or more radiant damage this way immediately contracts Solar Sickness. A creature afflicted this way gains four levels of Solar Sickness instead of one.

Creatures, plants, and flammable objects within the bomb's blast radius instantly catch fire. A creature on fire takes 2d8 fire damage at the start of each of its turns. If an effect would douse the fire, such as a creature patting fire or throwing water on the fire (typically as an action), the burning creature can make a DC 20 Constitution saving throw. On a successful save, the creature ceases burning.

A creature killed by the bomb's radiant damage leaves behind an animated shadow on the nearest surface to opposite the bomb, a fragment of its soul stored within the surface. The shadows act out the last two seconds before its demise in a repetitive loop. At GM's discretion, a speak with dead spell may allow for brief communication with the shadow as if it were a corpse.

Once the bomb has been activated, it can't be activated again until it has spent 4d6 days directly exposed to the Blighted Sun.

Zenthan Solstice. At the GM’s discretion, this bomb also has this property. If the bomb detonates on the Zenthan summer solstice, the bomb’s radius becomes 10 miles and its DC becomes 25 for that explosion.

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DESIGN COMMENTARY

No horrifying world is complete without an artifact and the villains capable of using it. Because it's an artifact, it's more interesting to describe how it can be used rather than its mechanics directly.

• The artifact is a bomb that detonates at one specific time, allowing a party to potentially stop it (or to write an adventure with a time limit). An example of the villains who might use it are the Daybroken, sun paladins. The damage dealt by the bomb is intentionally set so that an ordinary person could theoretically survive it without contracting Solar Sickness — truly the one-in-a-million prophesized to survive it.
• Another use is the aftermath. Sentient shadows reanimating after their death serve as a horrific backdrop to an evil plot, and offers some roleplay/exploration moments to trace the source of the blast.
• Of course, preventing the recharge of the cube can also be an adventure in itself.
• The Zenthan summer solstice is a decade-event, another avenue to design an adventure around prevent a massive world-ending weapon.
• And finally, there's potential clues to whatever divine relic was placed into this cube, from before the sun became a Blight.

Bombs and the sun is usually a natural sphere, but I wanted to design something to contrast that so that it would be more unnatural. The result is a lovely cube with cracks in it that makes it appear to struggle to keep itself together. The solar flaring was a massively difficult task to render (because in reference photos, it's usually backdropped against the black of void), so I eventually had to just stop and call it a day. A bit of motion blur helped smooth out the weirdness.