'A shard of the shattered Elden Ring. Grants the blessing of an equipped Great Rune upon use. Even if no Great Rune is equipped, it will slightly increase maximum HP upon use. It is said that the lower arch of the Elden Ring receive its bounty, and this is a shard of one such arch.' Rune Arcs are the smallest pieces of the canon's central artefact. The Elden Ring, when Marika shattered it, scattered into Great Runes (held by demigods) and into countless smaller fragments, the Rune Arcs themselves. Each Rune Arc, when consumed by the Tarnished, activates an equipped Great Rune's blessing for one death's worth of life. Without a Great Rune equipped, the Arc gives only a small HP bump. With Godrick's Rune equipped: +5 to all stats. With Malenia's: healing-on-attack. With Mohg's: a bloody umbra over allies.

'With the Great Rune menu, you can equip Great Runes that have had their power restored. You can use a Rune Arc to give even greater benefits to your equipped Great Runes.' The lore-frame the canon hides in the Rune Arc description is humbler: even the lower arch of the Elden Ring, the least exalted part of the artefact, is said to have received its bounty, and each Arc is a shard of one such arch. The mechanic-frame is that helping another Tarnished defeat a boss rewards you with an Arc, a rule of play the game never grounds in lore. Both frames make the same quiet point: blessing was never reserved for the Ring's summit and its Great Runes; even the smallest shard still carries a measure of the Elden Ring's grace.