Guide to Durandal "Reign Solar" in Honkai Impact 3rd: Builds, Teams & Advanced Tactics

Durandal’s S-rank battlesuit "Reign Solar" is a Stellar-type Fire DPS that dominates with sunspot mechanics, burst nuking, and team-wide buffs through solar energy manipulation. This guide covers optimal builds, rotations, and strategies for Memorial Arena, Superstring Dimension (SSD), and Elysian Realm.  

🔥 1. Core Mechanics & Playstyle  

Key Abilities  

- Sunspots (日斑):  

  - Generated by Charged Attacks or Resonance Skill. Detonated by Ultimate for massive AoE Fire DMG (up to 1,500% MV at max stacks).  

- Resonance Skill: Solar Prominence:  

  - Dash attack that applies "Solar Brand" (enemies take +25% Fire DMG). Triggers Sunspot Overflow at 3+ sunspots.  

- Ultimate: Corona Ignition:  

  - Consumes all sunspots for escalating AoE nukes. Grants "Daybreak" state: Charged Attacks generate 2× sunspots for 15s.  

- Team Synergy:  

  - "Stellar Beacon": Allies gain 15% Total DMG for each sunspot detonated (max 45%).  

Role Breakdown  

- Burst DPS: Sunspot detonation nukes groups/elites.  

- Fire Enabler: Solar Brand amplifies team Fire DMG.  

⚙️ 2. Optimal Gear & Stats  

Weapons  

| Weapon | Role | Key Effect |  

||-|-|  

| Solar Flare (BiS) | Hypercarry | +50% Sunspot DMG; Ultimate crits apply Solar Brand. |  

| Surtr's Grasp | F2P Alternative | +30% Charged ATK DMG; sunspot generation +40%. |  

| Star of Eden | Hybrid | Sunspot detonations restore 12 SP. |  

Stigmata  

- Reign Solar (4pc BiS):  

  - 2pc: Fire DMG +25%.  

  - 3pc: Sunspot detonations reduce Ultimate CD by 3s; Daybreak duration +8s.  

- Alternatives: Thales TB + Leeuwenhoek M (burst focus).  

- Main Stats: ATK/CRIT DMG (Time) → Fire DMG (Goblet) → CRIT Rate (Circlet).  

- Substats: CRIT Rate (70%+) > CRIT DMG > ATK% > SP Regen (130% min).  

👥 3. Team Compositions  

Fire Burst Core  

| Character | Role | Synergy |  

||-|-|  

| Durandal (Reign Solar) | Main DPS | Sunspot nuking + Solar Brand. |  

| AE (Azure Empyrea) | Support | Elemental Breach (-50% Fire RES) + SP regen. |  

| Raven | Sub-DPS | Fire DMG buff + off-field burning. |  

- Rotation:  

  1. AE: Ult → Combo ATK (trigger RES shred).  

  2. Raven: Deploy crows.  

  3. Durandal: Charged ATK (3 sunspots) → Ultimate → Daybreak spam.  

Stellar Synergy Team  

- Durandal + Kiana (Blazing Fortuna) + Eden:  

  - Kiana: Life Link amplifies sunspot DMG.  

  - Eden: SP battery for Ult spam.  

🎮 4. Advanced Playstyle  

Burst Rotation  

1. Sunspot Generation: 3× Charged ATK → Resonance Skill (max sunspots).  

2. Debuff Setup: Apply Solar Brand via Resonance Skill.  

3. Nuke Phase: Trigger Ultimate → Spam Charged ATKs in Daybreak.  

4. Reset: Swap to supports to recharge SP.  

Key Techniques  

- Sunspot Stacking: Use Charged ATK → Dash cancel for faster generation.  

- Brand Extension: Time Ultimate to refresh Solar Brand duration.  

- Energy Optimization: Pair with AE for SP efficiency.  

🌌 5. Elysian Realm Builds  

Recommended Signets  

- Solar Core : Sunspot detonations +100% DMG; max stacks +3.  

- Daybreak Extension: +10s duration; sunspots generate SP.  

- Support Signets: Elysia I (Ult CD -40%) + Kalpas II (HP trade for DMG).  

Boss Strategy  

- Vs. Herrscher of Dominance: Save Ultimate for clone phase; sunspots clear mobs instantly.  

⚠️ 6. Constellation & Investment  

- C0: Viable with F2P gear.  

- C2: Daybreak sunspots apply Solar Brand; SP cost -30%.  

- C6: Ultimate resets Daybreak duration; sunspot cap +5.  

- Farm Priority:  

  - Fire Shards: Universal Mirage Stage 6.  

  - SP Chips: Foundry crafting.  

💎 7. Pros & Cons  

| Strengths | Weaknesses |  

||-|  

| Top-tier AoE burst vs. groups | Single-target reliant on positioning |  

| Team-wide DMG amplification | SP-hungry without AE |  

| Flexible in Fire/Stellar teams | C2 needed for SSD efficiency |