Arknights: Heart of Surging Flame Retrospection Announcement And Event Summary!

Table of Contents

Heart of Surging Flame Retrospection
【Unbound Reflux】Banner
Skins and Furniture

Heart of Surging Flame Retrospection

The [Heart of Surging Flame Retrospection] event was announced with the following teaser:

The melody have been heard somewhere.

People gathered from all over the world are plunged into the vortex of music.

There is a story that has not been told yet.

In this enthusiastic tourist city.

Arknights Re-run Event, coming soon.

Here is the event page for the HOSF rerun details:

Heart of Surging Flame Retrospection - Event Page

Differences Summary

For those that participated in the first run of HOSF, here were the main differences:

Different "Featured Operator" Banner. [The Summer Guardians] Banner was not re-run, but instead a feature Banner with new Operators, [Unbound Reflux], was run
Significantly reduced rewards and event currency requirements for the Obsidian Milestone and Capsule Machines.
No Daily Missions that award event currency.
5 Capsule machines with less items and NO infinite capsule machine
1 new Story-only Operation.
Increased Sanity cost for Event Operations but the same ratio of currency drops to sanity spent (aka faster farming).
Operation progress is saved from previous event run, so first clear rewards are not available for Operations the player has previously cleared.
LimitedEvent items (Skins and Furniture) in the Obsidian Milestone and Capsule Machines that players have previously received will be replaced by a currency that can be used to purchase items in a special store.
Players still choose a band at the beginning of the event that will determine the BGM for the event and the conversation rewards from the capsule machines.
Unlike the original event, all band furniture will be available for purchase from the Furniture Store for 500 Furniture Parts or 3 OP (it will not be gained as a reward in the Obsidian Ladder)

Event Summary

For those that weren't here for the first event, the first choice you have to make is which Band to support during the festival. This will determine the BGM for your battles during the event, and which conversations are available from the gacha machine. For more information about the music and conversation rewards determined by the band choice, see this article:

Arknights: "The Band Choice" of the [Heart of Surging Flame] Summer Event. Choose Wisely!

This event requires players to run sanity-costing stages to collect [Siesta Obsidian] and [Obsidian Festival Tickets]

Siesta Obsidian

Obsidian Festival Ticket

[Siesta Obsidian] Milestone

[Siesta Obsidian] earns players rewards via a collection ladder. Here is the reward summary and the page with the full ladder details:

Heart of Surging Flame Retrospection - Siesta Obsidian Rewards

Casual Vacation HDm06

Note:

Do not over-farm [Siesta Obsidian]. More details below.
Any of the limited rewards (furniture and Skin) that the player already received in the original run will be replaced with [Intelligence Certs] which can be spent in its own section of the Cert Shop. Players running the event for the first time will receive the limited rewards and not the [Intelligence Certs].
In the original run, the band-exclusive funiture was awarded through this milestone, but in the rerun all furniture pieces are available for purchase in the Furniture store for 500 parts or 3 OP.

Capsule Machines (Reward Gacha)

Players must run event stages that cost [Obsidian Festival Tickets] to collect [Obsidian Festival Token] which can be used for "pulls" on the Capsule Machines.

Obsidian Festival Token

Here is the reward summary and page with the full list of rewards for the rerun Capsule machines:

Heart of Surging Flame Retrospection - Capsule Machine Rewards

Notes:

The rerun machines are not infinite, so do not overarm the [Obsidian Festival Tickets]. (more info below)
[Intelligence Certs] will be awarded instead of limited items.
If you have full potential Ceylon, her Tokens can be traded for Yellow Certs, just like any other Operator.

Intelligence Certs Store

As stated in the previous sections, players that have already acquired limited items (like furniture) in the previous run will be awarded [Intelligence Certs] that can be spent in the store (similar to the Grani rerun). The following new items will be added:

There were enough Intelligence Certs given to clear this shop. More details can be found here:

[Intelligence Certs] Shop For Rerun Events

Farming Guide

As stated earlier, since the stages do not drop elite materials, it is important to not over-farm for event currency. Here is a summary of the farming guide:

Clear all Event Operations and Challenges once.
Farm OF-7 until you have farmed 1060 [Siesta Obsidian] using ~530 Sanity. Don't over-farm [Siesta Obsidian]. To get this exactly, run:
- For New Players:
  - OF-1, OF-3, OF-4, OF-6: 1 time (first clear only)
  - OF-2: 3 times (first clear + 2 more times)
  - OF-7: 15 times (first clear + 14 more times)
- For Returning Players:
  - OF-7: 17 times (1020 Obsidian)
  - OF-6: 1 time (28 Obsidian + 7 Tickets)
  - OF-1: 1 time (12 Obsidian + 3 Tickets)
Farm OF-8 40 times (32 times for new players) with 1200 Sanity (940 for new players) to get 600 [Obsidian Festival Ticket] (470 for new players). (NOTE: since the number of Tokens you get from OF stages are variable, you may need more or less runs depending on your luck)
Farm OF-F4 ~35 (~32 for new players) times with [Obsidian Festival Ticket] to get 2800 (2560 for new players) [Obsidian Festival Token] for the Capsule Machines. (NOTE: since the number of Tokens you get from OF stages are variable, you may need more or less runs depending on your luck)
If you are new/low level, all OF stages give the same Obsidian/Ticket per sanity, higher sanity stages just make faster farming. OF-F3 is the same Token per ticket ratio as OF-F4, just slower farming.
The order you wish to farm the Event currency is up to you.
Pure f2p will Definitely have enough Sanity to clear both shops + Weekly Annihilation, so no worries!
There is NO infinite machine for the rerun.

For more details on how these numbers were obtained, and details on the drops of all the stages, see this page:

Arknights: Heart Of Surging Flame Retrospection (Rerun) Event Operations And Farming Guide

Here are the first-clear rewards for the event Operations:

【Unbound Reflux】Banner

For the run of this event on CN, the 【Unbound Reflux】Banner was available, that featured Thorns. However, it greatly upset CN players to have a new Operator feature banner and new skins without having event nodes that offered Originte Prime. This left some f2p players with no currency to pull on the new banner or acquire skins. Also, the lack of much lore around the new Operators and them not being included in the story left some players feeling like the depth of the world was being compromised to push out more Operators. The developer admitted this was a mistake, and so re-ran the banner at a latter date and promised never again to introduce a new operator banner along with a rerun event.

It is unclear wether Global will repeat this mistake and run the Thorns banner along with the rerun, and then bring the banner back again later, or if they will learn from the mistake and not run a new Operator banner with a rerun event. If the latter is true, then we will probably get a rerun of the Schwarz banner.

In case we get it, here is the contents of the Thorns banner:

Featured Operators:

Rarity	Operator
6★ Rate Up	Thorns - Ranged Guard
5★ Rate Up	Andreana - Long-Range Sniper Provence - Close Range Sniper
4★ Rate Up	Jaye - DP-Drain Specialist