Memorial Arena, as its name implies, is a game mode where Captains can face off against challenging bosses from previous encounters. The virtual battlefield uses data to recreate enemies and have them battle with Valkyries with the aim of increasing Valkyries' battle prowess. Memorial Arena runs from Tuesday, 04:00 to Monday, 02:00 every week. Between Monday 02:00 and Tuesday 04:00, results are calculated and rewards are distributed.
Battling Enemies[ | ]
Enemies in the Memorial Arena have their memory upgraded with ranks "C, B, A, S, SS" with each letter corresponding to a different difficulty level. Once a Captain has defeated an enemy at a certain difficulty level, they will automatically move up to the next difficulty level. After certain difficulty levels, enemies in the arena will begin to use different attacks and sometimes even special ultimate skills when damaged enough.
The Exalted bracket also features 2 SSS rank Bosses (as of Patch v6.1, including 20% UP one, and one at the middle) which the captain can challenge to get bonus score-based rewards. In addition, there's also Buffed Mode that can be enabled before the encounter. That will overall benefit their team during the battle, in exchange for the score loss at the end of the fight.
Locked Gear & Valkyrie[ | ]
Once a valkyrie or a gear is used for a Memorial Arena boss, the valkyrie or gear is locked to that boss. In addition, unawaken and awaken forms of the same valkyrie cannot be used for the same boss -- even if they are used in different attempts. The lock is finalized when an attempt is registered -- ie. by either defeating a boss or being defeated without exiting early. For example, if Valkyrie Pledge equipped with Oath of Judah is used to defeat C Rank RPC-6626, both Valkyrie Pledge and that particular Oath of Judah will not be usable on any other boss; in addition, Luna Kindred -- Valkyrie Pledge's awaken form -- cannot be used for RPC at any rank. This, however, does not restrict a different Oath of Judah in the captain's inventory to be used for another boss.
Scoring[ | ]
The maximum score for each boss goes up as a captain beats a higher rank of that boss. The actual score is reduced by the amount of in-game arena time the captain spends beating the boss of that rank (Time spent on previous rank are not counted). At SS rank, every in-game second spent equates to 53-point reduction, and each SS rank boss allows for a maximum score of 31946 which equivalent to defeating them with 0-second wasted. Captains can challenge the same boss again at SS or SSS (Exalted only) rank. Only the highest score achieved will be counted.
Each rotation there is also one boss that gives a bonus 20% to the score achieved against it.
During a boss encounter, if a captain is defeated either by losing all valkyries or by timer running out, the captain will lose a challenge attempt. A score based on the remaining health of the boss and its rank will be awarded -- although much less than the score from defeating the boss. If the captain abandons during an encounter, no score is awarded but no challenge attempt is consumed either.
Brackets[ | ]
Captains are placed into 4 different brackets based on their captain level.
- Basic (Lv.38-55): 2 bosses; 4 attempts per day.
- Elites (Lv.56~69): 2 bosses; 4 attempts per day.
- Masters (Lv.70-80): 3 bosses; 5 attempts per day.
- Exalted (Lv.81-88): 3 bosses; 6 attempts per day.
If a Captain levels up during a rotation, they will not move up in bracket until the next rotation.
The difficulty of the bosses increase significantly as a captain moves up in brackets. For example, a Rank S boss may pose a significant challenge for a level 70 captain in Masters even though the captain can achieve good scores with same boss at Rank SS previously in Elites. The additional 3rd boss may be out of reach due the sudden requirement for a 3rd team of valkyries along with their gears. Memorial Arena is thus one of the reasons that it is advisable to slow down leveling above level 50 or level 60 -- depending on active events of the time.
Arena LITE[ | ]
The permanent LITE function is currently available in Exalted bracket. Once the captain defeat the UP boss at SS or SSS rank, they can use that to auto-defeat bosses on the next rotation up to S or SS rank respectively, at the cost of one attempt per use.
Rewards[ | ]
At the end of each week, captains receive tier rewards based on their total scores from all bosses as well as rewards based on their relative ranks in their respective tiers. Ancient Willpowers 
and Ancient Legacies 
, which can be obtained from Lv70 onward, received from the arena are used in War Treasury.
Score rewards are accumulative. A captain will receive rewards from all reward tiers up to their score. In contrast, captains only receive ranking rewards of their interval. For example, a captain with a total score that ranks at 12% in Basic will receive rewards tier 12.50% as 12% is between 5.00% and 12.50%. But the captain does not receive rewards for intervals below 12.50%.
Basic Score Rewards[ | ]
| Total Score | Rewards |
|---|---|
| 1 Kill |  ⨯40000 ⨯3 ⨯3 |
| 2 Kills | ⨯44800   ⨯2 ⨯3 |
| 3 Kills | ⨯40 ⨯4 ⨯420 |
| 4 Kills |  ⨯2 ⨯4  ⨯2 |
| 5 Kills | ⨯55000 ⨯5 ⨯4 |
| 6 Kills | ⨯50 ⨯67200 ⨯5 |
| 7 Kills | ⨯70000 ⨯6 ⨯420 |
Basic Ranking Rewards[ | ]
| Rank | Rewards |
|---|---|
| Top 0.10% | ⨯10 ⨯35 |
| Top 1.30% | ⨯7 ⨯28 |
| Top 5.00% | ⨯6 ⨯20 |
| Top 12.50% | ⨯5 ⨯12 |
| Top 25.00% | ⨯3 ⨯7 |
| Top 50.00% | ⨯2 ⨯3 |
Elites Score Rewards[ | ]
As of Patch 5.1,
| Total Score | Rewards |
|---|---|
| 1 Kill | ⨯55000 ⨯4 ⨯4 |
| 2 Kills | ⨯67200 ⨯2 ⨯4 |
| 3 Kills | ⨯40 ⨯5 ⨯420 |
| 4 Kills | ⨯3 ⨯5 ⨯1 |
| 5 Kills | ⨯70000 ⨯6 ⨯4 |
| 6 Kills | ⨯50 ⨯6  ⨯1 |
| 7 Kills | ⨯85000 ⨯6 ⨯840 |
Elites Ranking Rewards[ | ]
| Rank | Rewards |
|---|---|
| Top 0.10% | ⨯13 ⨯45 |
| Top 1.30% | ⨯10 ⨯34 |
| Top 5.00% | ⨯7 ⨯24 |
| Top 12.50% | ⨯6 ⨯16 |
| Top 25.00% | ⨯5 ⨯9 |
| Top 50.00% | ⨯3 ⨯5 |
Masters Score Rewards[ | ]
As of Patch 5.1,
| Total Score | Rewards |
|---|---|
| 1 Kill | ⨯40000 ⨯5 ⨯3 |
| 2 Kills | ⨯89600 ⨯3 ⨯5 |
| 3 Kills | ⨯45000 ⨯5  ⨯1 ⨯840 |
| 4 Kills | ⨯40 ⨯5 ⨯1 |
| 5 Kills | ⨯50000 ⨯5 ⨯1 ⨯3 |
| 6 Kills | ⨯4 ⨯5 ⨯2 |
| 7 Kills | ⨯60000 ⨯6 ⨯1 ⨯840 |
| 8 Kills | ⨯50 ⨯7 ⨯2 |
| 10 Kills | ⨯60000 ⨯7 ⨯1 ⨯5 |
Notes: Memorial Arena originally rewarded Gyakushinn Miko Souls, this was changed in a later update into Imayoh Ritual Souls.
Masters Ranking Rewards[ | ]
As of Patch 5.1,
| Rank | Rewards |
|---|---|
| Top 0.20% | ⨯16 ⨯55   ⨯1  ⨯40 |
| Top 2.00% | ⨯13 ⨯40 ⨯40 |
| Top 7.00% | ⨯10 ⨯30 ⨯40 |
| Top 17.00% | ⨯8 ⨯20 ⨯40 |
| Top 35.00% | ⨯6 ⨯12 ⨯40 |
| Top 65.00% | ⨯5 ⨯7 ⨯40 |
Exalted Score Rewards[ | ]
As of Patch 5.1,
| Total Score | Rewards |
|---|---|
| 1 Kill | ⨯60000 ⨯5 ⨯1  ⨯4 |
| 2 Kills | ⨯5 ⨯5 ⨯1  ⨯5 |
| 3 Kills | ⨯70000 ⨯6 ⨯1 ⨯840 |
| 4 Kills | ⨯50 ⨯5 ⨯1  ⨯40 |
| 5 Kills | ⨯80000 ⨯5 ⨯1 ⨯5 |
| 6 Kills | ⨯6 ⨯6 ⨯1 ⨯5 |
| 7 Kills | ⨯90000 ⨯7 ⨯1 ⨯840 |
| 8 Kills | ⨯50 ⨯8 ⨯1 ⨯60 |
| 10 Kills | ⨯90000 ⨯8 ⨯2  ⨯5 |
SSS Boss Score Rewards[ | ]
As of Patch 5.1,
| Total Score | Rewards |
|---|---|
| 24,000 | ⨯2 ⨯4 |
| 38,400 | ⨯20 ⨯4 |
| 40,800 | ⨯2 ⨯4 |
| 43,200 | ⨯4 ⨯8 |
| 46,080 | ⨯4 ⨯8 |
Exalted Ranking Rewards[ | ]
As of Patch 5.1,
| Rank | Rewards |
|---|---|
| Top 0.20% | ⨯20 ⨯65  ⨯1  ⨯1  ⨯50 |
| Top 2.00% | ⨯20 ⨯65 ⨯1 ⨯1 ⨯50 |
| Top 7.00% | ⨯16 ⨯48 ⨯50 |
| Top 17.00% | ⨯13 ⨯36 ⨯50 |
| Top 35.00% | ⨯10 ⨯25 ⨯50 |
| Top 65.00% | ⨯7 ⨯15 ⨯50 |
War Treasury[ | ]
On September 11th, 2018, the fabled War Treasury appeared! Not only can you acquire Knight Moonbeam and Lightning Empress fragments (which increase in cost after each purchase), but also a variety of other fragments, items, and weapons!
On April 18th, 2019, Blood Rose, Phoenix and Sixth Serenade fragments were introduced, KMB and LE fragments weekly purchases were increased from 5 to 6, price increase was changed(Now up to 18 instead of 20) and Yae Sakura Cask weekly purchases were increased from 3 to 8.
On May 23rd, 2019, Molotov Cherry Fragments were introduced.
The currencies used in the War Treasury are 
, which can be purchased mainly in War Treasury and BP Arsenal, and can be obtained from Memorial Arena and Weekly Quiz, and , which can be obtained normally from Abyss and Memorial Arena once reached Lv70.
Items[ | ]
Valkyries[ | ]
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