The Ashblazing Grand Duke
The Ashblazing Grand Duke is a relic set in Honkai: Star Rail with the following effects:
The 4-piece grants a flat 20% Follow-Up ATK DMG boost plus stacking ATK on repeated Follow-Up hits, making it the best-in-slot set for the entire Follow-Up ATK archetype.
Increases the DMG dealt by Follow-Up ATK by 20%.
When the wearer uses a Follow-Up ATK, increases the wearer's ATK by 6% for every time the Follow-Up ATK deals DMG. This effect can stack up to 8 time(s) and lasts for 3 turn(s). This effect is removed the next time the wearer uses a Follow-Up ATK.
The block below gathers main-stat recommendations by character ROLE (not tied to one character) — most EN aggregator sites push this to a separate build page; here it sits right on the set page.
Flat HP — fixed, not selectable.
Flat ATK — fixed, not selectable.
Standard DPS: CRIT Rate or CRIT DMG. Support/healer roles: HP% or Outgoing Healing.
ATK% for most DPS; SPD if the team needs to act first or for support/CC roles.
General substat priority: CRIT Rate > CRIT DMG > ATK% > SPD — reorder for the specific character's role; this is only a safe default.
How to read this relic set page
Cavern Relics have 4 pieces: Head and Hand always carry fixed flat stats (HP and ATK), so only Body and Feet have a random main-stat you actually choose. The 2-piece effect unlocks with 2 out of 4 pieces from the same set; the 4-piece effect is stronger but needs all 4 and usually has its own trigger condition — read the exact text above before committing. Planar Ornaments only have 2 pieces (Planar Sphere + Link Rope) and only ever have one 2-piece effect, there is no 4-piece version.
The two types also differ in where you get them: Cavern Relics drop from the Cavern of Corrosion and cost Trailblaze Power per run; Planar Ornaments come from the Simulated Universe or Divergent Universe, which do NOT cost Trailblaze Power — you trade for them with items or completion rewards instead. A full loadout usually combines one 4-piece Cavern set (or two different Cavern sets at 2 pieces each) with one 2-piece Planar set — go 4-piece when that set gives a large, reliable damage buff, and mix 2+2 when you need to stack several smaller stats (e.g. ATK% from one set plus Elemental DMG% from another).
The "who should use this" list is pulled from cross-sourced build consensus and updates automatically as the meta shifts, it is not hand-picked. See the full set table on the Relics page, or check terms in the HSR Glossary.