| Category | Marvels, Artifacts |
| Type | legendary artifact |
| Location | varies |
| Owners | by creator |
| Built | varies |
When activated, an Entropy Arch becomes a bridge between wherever it is opened and the Chaos realm. The first of these devices were constructed during the Creation War ( 1486 DE - 8777 DE ) . Faced with the vast expanse of space, the primordials built entropy arches as a means of creating stable Rifts that proved undetectable by weave spiders.
Those distant systems are the domains of the Creationists. In that realm, they construct worlds and populate them with life. They impose order upon chaos. This practice must be halted immediately, lest those seeds become their formidable legions.
The Master of Tides, inscribed upon the Tâchan Entropy Arch - "Law Evolves"
An entropy arch is a legendary, artifact-like device of immense power. The primary component for its creation is the Entropy Fragments. The construction of these rift-generating devices has historically incited devastating conflicts. During the Creation War, the gods and primordials clashed across Bal-Kriav and other realms, with the primordials utilizing entropy arches at locations such as Regadnîn and Tâchan. When the arches were activated, primordial armies poured forth, engaging in battle with Covenant forces. One of the most extensively used entropy arches was situated at the base of Piranoth Cyst, which was ultimately destroyed by the angel Naraz-Nâru using three relics collectively known as Sig Mak Gan.
Following the Creation War, two significant mortal conflicts arose from the construction of an entropy arch: the War of the Fragments and the Cinazan Front.
In the year 1486, the Altocumuli Empire reclaimed six Entropy Fragments, which they subsequently utilized to construct an entropy arch.
The opening of these chaos arches establishes a passageway between Chaos and a realm. Raw chaos surges through it like a thousand raging tempests. This tidal wave of energy is so formidable that nothing is believed to withstand it. It can shear the landscape, transforming vast expanses into fragments of their former selves. A lake may levitate or plunge into the ground as if impossibly dense, earth may ascend skyward or crumble into dust swept away by the winds.
Arcana, prior to ascending to divinity, from a Scroll of Dawn - "The Workings of a Chaos Arch"
When an entropy arch is first opened, a surge of entropic energy pours forth. The source of this blast wave emanates from the rift's other side, the realm of Chaos. The best documented occurrence of this event transpired on 7 Witchrite 1832. On this day, an Entropy Arch was dropped into the heart of Sapthiladân. This descent, amid a hail of cannon fire, magic, and arrows, was executed by the Pillar of Horns, an enormous voidship that delivered the Entropy Arch to the city's central square. The Arch then activated and opened its portal to Chaos. This event reduced a substantial portion of the city to rubble. The blast wave continued past the city, striking the Kerthjorg highlands, where the chaotic energies sheared a string of mountains as effortlessly as a hot knife cuts through butter. The result of this incident was the creation of the Skyldr-Kerthjorg sky islands.
The entropy arch utilized at Sapthiladân was constructed with entropy fragments removed from the Pinnacle of Chaos. Shortly after the rift's opening, the vanguard of the 3rd Horde of Chaos, led by Drachmon, began to arrive on the world Bal-Kriav. This army bolstered the forces of the Flux Pact engaged in the Cinazan Front against the Khazarar Empire.
In the Creation War, primordials favored utilizing Entropy Arches over conjuring Rifts. This preference arose from the fact that Rifts represent tears in the Web of Magic, which invariably draw the attention of the Web's unyielding protectors - the weave spiders.