Death Dealer Ray (DDR) is a pretty simple fight so long as you have Schniel. All of the mechanics were pretty much designed around him, and he’s easily the most important unit on any team. I’ll go over the boss’s skills, the general fight mechanics, team comps+stats, and have links to a couple videos at the end for anyone who wants a more visual guide.

Mechanics

The fight is similar to previous bosses, where you wait for the boss to use S2 and play a specific mechanic which puts you into the break phase. For this one, after DDR uses S2 and gives the adds the Overload effect, you need to use an AoE attack that has Silence, Provoke, or Redirected Provoke before the adds take a turn. This will kill the adds and also increase the Exhaustion gauge by 60%. While waiting for the boss to use S2, you’ll need a good full cleanse, and sustain. Every time a unit, ally or enemy, takes a turn, all of your units will lose a bit of their current HP. This isn’t active during the Break phase so you can at least heal up during that. DDR’s S1 targets the unit in the back slot, who is going to be a pretty squishy unit, and increases their cooldowns by 2 turns. So you’ll need enough sustain to survive until DDR uses his S2. His S3, which he uses at the start of the fight and after each break phase, is an AoE strip that applies 2 venoms and deals extra damage. You’ll want to instantly cleanse the Venoms and make sure you have enough Health to survive the extra damage. His passives make him ignore EffRes, gives him 10% CR everytime one of your units moves, and disables Focus, Fighting Spirit, Dual Attacks, as well as Counterattacks. The adds don’t do much, they’re immune to all debuffs except for Silence, Provoke, and Redirected Provoke. If you don’t hit with the debuffs before they move while they have Overload though, they’ll use a very high damage single target attack that’ll just about kill any unit.

For Auto, you'll just want to make sure that your AoE debuffer doesn't use their skill until after DDR uses his S2. This isn't too hard to do if you just make your AoE base speed, and your two supports really fast. You'll also of course need to make sure you have enough sustain.

Schniel

Schniel is a core part of this boss rotation, since the entire fight was designed around him. His S2 cleanses the Venoms from DDR’s S3, and the Soul Weaver Prayer buff turns him into a damage dealer. He doesn’t really have any good replacements, the best you’ll get is tossing Achates in the frontslot since she has good sustain but you’ll lose a ton of damage. You’ll want to build him as a DPS with Attack, Crit Chance, Crit Damage, and maybe Speed. For his artifact, POS is good if you have that, otherwise give him a damage boosting artifact like Symbol. For the top end scores you’ll want Schniel to be fast enough to lap your back-slot unit in the break phase ideally, but if you’re just aiming for top 5% his speed doesn’t really matter too much. While his S3 in the break phase scales off of the back-slot unit’s Attack, it does seem to also factor in his attack a bit. He’s going to be the vast majority of our damage thanks to all the bonuses he gets. This also makes him a good candidate for Grace of Growth if you want the extra 2 damage nodes in his S3, but it’s not that important unless you’re aiming for Top 100 so you could save it for a different unit instead.

Healer

Next up you’ll want a healer, because Schniel doesn’t actually heal us. The easiest choice is going to be Achates, you can spam S3 S2 S3 as usual and she’ll provide a ton of sustain. This also lets her skip her turns in the break phase without you really having to put any effort in. You’ll want to build her with a good amount of Speed and then HP. You can give her an Attack boosting artifact like War Horn, if you need more sustain then you can give her a healing artifact like Rod of Amaryllis. The top scores right now are using Emilia, who is much harder to use due to her low sustain, but her CR push, Attack buff, and Attack imprint are extremely valuable. She needs to be on Rod of Amaryllis since she doesn’t heal much.

AoE Silence/Provoke/Redirected Provoke

For the AoE silence/provoke/redirected provoke unit theres a few options. Yufine has an AoE Silence on her S2 but it needs Molas to hit 100% (as well as an EE), good choice if you already have it enhanced. Kawerik has a AoE Silence on his S3, 100% before any Molas. It’s 5 turns at base, 4 turns after Molas, but you can make use of Eticas Scepter or Achates S2 to help reduce the cooldown if you haven’t enhanced his S3. Fairytale Tenebria has an AoE Redirected Provoke on her S3 with the same conditions as Kawerik, 100% base with a 5 turn cooldown, 4 turns after molas. Finally there’s Cecilia who has an AoE Provoke on her S3, though it also requires Molas to hit 100%. The other AoE debuffers don’t have 100% chance so one of these 4 will be your best choice. For these units you’ll want to build them full damage ideally since usually they take 1 turn during the Break Phase. It’s only 1 turn and they don’t deal that much damage either way so you could make them a bit bulkier if you want, though you’re only be reducing the damage from the add’s AoEs. Their speed will wary based on your setup, I went with a base speed Kawerik, but you’ll want to use whatever lets you AoE debuff in time before the adds move in the Overload phase. For Artifact you can just give them a stat boosting artifact unless you need Eticas Scepter for the mages.

High Attack DPS

Lastly there’s our back-slot unit. This unit can be anything really, just a unit with high base attack that you slam a ton of Attack into. Ram is the most common unit since her S2 gives her a bunch of bonus attack. Cermia is a much more accessible alternative. The top scores use Luluca right now, since Luluca’s S2 lets her skip one of her turns in the break phase and get an extra Schniel S3 in, but this isn’t necessarily unless you’re aiming for top 3. For the build, you’ll just want to stack as much Attack on them as possible with minimum speed ideally and Cruel Mischief as the artifact. CritC and CritD aren’t that important.

Videos

If you want to see examples of the runs you can see them in the links below.

Manual Top 100 Setup

Auto Top 5% Setup