This is a Castle Rush guide for Immortal Castle in Seven Knights Re:Birth. Covering Wednesday's Rachel Castle, Best Team, Best Hero, Strategy, Tips, and How to Get a High Score in 7K Rebirth.
Table of Contents
Immortal Castle Overview
| Enemy |  Rachel Rook Chancellor |
| Enemy Attack Type |  Physical |
| Status Effects Inflicted |  Burn |
| Effective Status Effects | None |
| Other Features | - Decreases Defense and All Attack Reduction - Physical Attack/Single-Target Skill/5-Target Skill Damage Resistance - Activates Berserk after 30 turns (Damage Dealt increases by 50% → increases to 100% → 200% → 500% over turns) |
Immortal Castle is one of Castle Rush's stages where you face the Seven Knights and earn points. It opens every Wednesday, and rewards are distributed daily at 12 AM (UST+0) based on Guild Rank, which is determined by the total points earned by all members.
 Tips! | Guild members who don't participate will not receive rewards. |
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Main Rewards
| Category | Rewards |
|---|---|
| Personal Rewards |  Guild Token Gold Key Castle Rush Challenge Medals |
| Guild Rewards |  Hero Ticket per Guild Rank Gold Box per Guild Rank Castle Rush Challenge Medals |
| Challenge Missions |  Key Bundle Leah Skill Enhancement Stone Gold Rare Hero Selector Hero Summon Voucher |
Castle Rush offers Personal Rewards, Guild Rewards, and Challenge Mission Rewards. For the Guild Reward's Hero Summon Card, higher Ranks increase the chance of obtaining Seven Knights, so work together with your Guild to achieve a high score.
| Tips! | You can also exchange 4000 Castle Rush Challenge Medals for a Seven Knights Summon Card at the Guild's Exchange Shop |
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Enemy Info
| Round 1 | ||
|---|---|---|
| Rook | Chancellor | Rook |
| Round 2 | ||
| Rook | Chancellor | Rook |
| Round 3 | ||
| Rook | Rachel | Chancellor |
Rachel in Immortal Castle inflicts Burn, All Attack Reduction, and Defense Reduction, making extended battles highly demanding. Meanwhile, Immortal Castle Rook and Chancellor can also inflict Burn and possess Physical Damage Resistance, making this stage difficult to clear without the right team setup.
Castle Rush GuideImmortal Castle Best Heroes
Burn Immunity
The enemy inflicts Burn. Without countermeasures, you'll be at a significant disadvantage, so make sure to include a hero with Burn Immunity. Yui works well as an early-game healer, but ideally, you should use Ariel, who can also boost your team's firepower.
Magic Attacks on 3-4 Enemies
Karma
Rin
Vanessa
CleoAll enemies in the Immortal Castle have Damage Resistance against Physical attacks, single-target skills, and 5-target skills, so focus on using magic attacks that hit 3–4 enemies. Ruri is highly recommended, but if you don't have her, it's best to develop the F2P hero Sera instead.
Buff & Debuffs
Biscuit
Lina
Vanessa
Yeonhee
AceWhen you enter the third round, use buffs and debuffs to increase your attacker's damage. It's recommended to apply buffs and debuffs with longer durations first.
Debuff Removal
Miho
Lucy
ChloeWhen Rachel uses Skill 2, it lowers your Defense and All Attack. This puts you at a disadvantage and makes it harder to raise your score, so remove the debuff immediately with a hero who can use Debuff Removal.
| Tips! | Lucy or Chloe are good early options for Raids and Power-Up Dungeons, but Miho is best, offering back-row Debuff Removal at 2 Transcendence. |
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Team Formation Examples
Premium Team
| Front Row | Front Row | Front Row | Front Row | Back Row |
|---|---|---|---|---|
 Ariel YuiBurn Immunity |  LinaHealer Def Debuffer |  BiscuitBuff Removal Def Debuffer (Flex Slot) |  MihoDebuffer Sub DPS |  Ruri YeonheeMagic Attack Main DPS |
F2P Team
| Front Row | Front Row | Front Row | Front Row | Back Row |
|---|---|---|---|---|
| Yui Burn Immunity Healer |  Chloe LucyDebuff Removal |  NohoBiscuitBuff / Debuffer | MihoAriel Sub DPS |  SeraMagic Attack Main DPS |
Optionally, you can place Miho or Ariel (Sub DPS) in the back row alongside the main DPS when using Balanced Formation, especially if they're well-enhanced.
Immortal Castle Tips & Strategy
Form Teams Effective Against Rachel
The key to victory is bringing heroes with Magic Attacks with 3-Enemy Target skills, Burn Immunity and Debuff Removal to counter Rachel, so adjust your lineup accordingly.
| Immortal Castle | |
|---|---|
| Boss & Mechanics | Boss Rachel uses attacks that inflict Burn, All Attack Reduction, and Defense Reduction. |
| Strategy | Bring a hero with Burn Immunity and a hero who can Debuff Removal, as reduced Attack lowers the points you earn. |
| Enemy Resistances | All enemies in Rachel's Castle Rush have Physical Resistance, Single-Target Attack Resistance, and Quintuple-Target Attack Resistance. |
| Recommended Heroes | Use Magic-type heroes with Triple-Target Attack skills to maximize points and clear waves efficiently. |
Use Protective Formation
Protective Formation is the recommended setup for Immortal Castle. At Level 20, it boosts Back Row heroes' Attack by 26% and grants Front Row supports and healers a 6.5% Defense increase. Other formations can also work, but require more investment into your characters and gear.
| Tips! | Make sure to enhance the formation level for increased back row and front row effect. The higher the Formation level, the better. |
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Use Skill Queue
Auto Skills offer convenience, but they don't always select the optimal skills in critical situations. It's best to use the Skill Queue to start with a buff, then monitor combat and manually activate skills as needed.
| Tips! | Strategically, queue buffs first, such as 'Barrier', then use priority skills manually to gain the upper hand. |
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Enhance Your Hero
Enhance your heroes' skills, ultimate, and power-up to +5. Prioritizing tanks and healers to boost their effectiveness and utility. Skill & Ultimate Enhancement materials can be obtained from Story Event rewards, the Shop, and the Infinite Tower.
| Related Articles | ||
|---|---|---|
| Power Up Heroes | Upgrade Equipment | Enhance Formation |
How to Get the Highest Score
Use Magic Heroes with 3-Target Skills
All enemies in Immortal Castle have Physical Resistance, Single-Target Attack Resistance, and Quintuple-Target Attack Resistance buffs. To increase damage output and achieve a high score, use Magic-type heroes with Triple-Target Attack skills.
Sustain is Optional
The core mechanic of Castle Rush is to maximize total damage within the turn limit, as scores are based on the cumulative damage dealt before the final turn. If your team can endure without heavy support, focus on offense and debuff removal instead to maximize score.
| Tips! | If your team struggles, bring a healer, debuffer, or crowd control to survive until the final turn. |
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Related Seven Knights Re: BIRTH Articles
▶Back to Top PageRanking Articles
| Ranking Articles | ||
|---|---|---|
 Best Hero Tier List |  Reroll Tier List |  Best Pet Tier List |
How To Reroll Fast?
Leveling & Ruby Farming Guide
Latest News & Updates
Daily Things to Do
Best Heroes and Teams
Advent Expedition Guide
Best Premium Shop Purchases
Best Low Rarity Heroes
The Root of the Storm Event
Should You Pull for Kyle & Aquila?
Children Chasing Stars Event
Brilliant Pumpkin Baskets Guide
Early Game Guide
Player Rank (Adventurer Skill) Guide
Enhance Guide
Equipment Powerup
Pet Guide
Formation Guide
Guild Guide
Party Guide
Gacha Animation Effects
Accessory Guide
Hero Stats Guide
Arena Guide
Coupon Codes
Infinite Tower Guide
Shop Items to Buy
Fodder Hero Guide
Tower of Trials Guide
7K Chess Guide
Equipment Preset Guide
Battle Statistics Guide
Recommended Relay Purchases Guide
Weakness Hit Guide & What is It?
Error Guide and How to Fix
Guild War Guide
Castle Rush Guide
Guardian's Castle Guide
Fodina Castle Guide
Death Castle Guide
Ancient Dragon's Castle
Blizzard Castle Guide
Death Guide
Hell Castle Guide
Destroyer Gaze Guide
Ox King Guide
Iron Devourer
Raid Battle Guide
How to Beat Teo
Burn Guide
Paralysis Guide
Bleed Guide
Freeze Guide
Stun Guide
Petrify Guide
Shock Guide
Sleep Guide
Concussion Guide
Debuff Types Guide
Confusion Guide
Poison Guide
