Rennac

Weapon: Vicious Dagger+ (+SPD)

Assist: Positional Assist / Flexible

Special: Glimmer / Moonbow / Luna

Passive A: Atk/Spd Solo / Sturdy Impact / Mirror Impact 

Passive B: Watersweep / Windsweep 

Passive C: Joint Drive Skills / Time’s Pulse / Flexible

Sacred Seal: Atk/Spd Solo / Swift Sparrow / Sturdy Blow / Mirror Strike / Heavy Blade / Flashing Blade

• This is an all-purpose offensive set meant to maximize Rennac’s damage and safety through exploitation of his native Vicious Dagger — a phenomenal inheritable weapon that allows him to negate effects that would otherwise negate his double, akin to Null Follow-Up. Taking a +SPD or +ATK IV naturally lends itself well for this playstyle.
• Thanks to Vicious Dagger’s powerful effect, Rennac is free to wield Watersweep or Windsweep in his B skill to entirely negate counterattacks from all magical or physical threats altogether while still being able to double normally; this essentially transforms him into a pseudo-Firesweep nuke, though only against specific enemy types.
  • The main consideration then becomes which of the two skills to use. 
  • Although Windsweep is the more commonplace and traditional route to go, it’s worth keeping in mind that Rennac’s physical durability is actually pretty solid. Supplemented by a complimentary skill like Sturdy Impact or ally support, it’s entirely possible to elevate his physical survivability to instead equip Watersweep to mitigate his considerably worse magical bulk.
  • Ultimately, though, both are great options — it all comes down to a matter of personal preference and skill availability.
• Rennac’s native Atk/Spd Solo is the premium offensive A skill to use here if heightening his damage is preferred over everything else. Otherwise, you could also consider between Sturdy or Mirror Impact to make initiations less dangerous via their respective +10 defensive boosts and enemy follow-up denial; they don’t offer anything for Rennac’s own follow-up, though, so boosting his Speed through outside means is appreciated. 
• Joint Drive skills are universally appreciated C skills – they essentially provide stats for free given their easily-fulfilled proximity requirement, and Rennac could always use another helping of Attack or Speed. Time’s Pulse is also an option to hasten his Special activation, but his C skill is generally flexible overall. Just don’t use Def Smoke as it is redundant with the innate debuffs of dagger weapons. 
• Any Sacred Seal that augments Rennac’s key stats works perfectly well here; this ranges from traditional stat-boosters like Atk/Spd Solo and Swift Sparrow to Sturdy Blow and Mirror Strike if more raw bulk is preferred. The Flashing Blade or Heavy Blade Sacred Seals also work well to let him access his Special faster akin to Time’s Pulse.

Weapon: Quick Dagger (+ATK) / Pumpkin-a-Box (+ATK) / Barbed Shuriken (+ATK)

Assist: Positional Assist / Flexible

Special: Blazing AoE Special

Passive A: Flashing Blade / Heavy Blade / Life and Death / Fury

Passive B: Special Spiral 

Passive C: Time’s Pulse / Def Smoke / Savage Blow / Flexible

Sacred Seal: Quickened Pulse / Life and Death / Flashing Blade / Heavy Blade / Hardy Bearing

• This build highlights Rennac’s Player Phase performance yet again, though this time this places a greater emphasis on his OHKO capabilities through rapid and powerful Special activations. A +ATK is ideal to fully heighten his raw firepower. 
• This set plays out as you would expect a traditional AoE-spam build to — despite their high cooldowns, such Specials can be consistently activated in every round of combat through the combination of Special Spiral and one of Flashing Blade, Heavy Blade, or Barbed Shuriken. 
• Rennac has three main weapon choices in Quick Dagger, Pumpkin-a-Box, and Barbed Shuriken. 
  • Quick Dagger is excellent to provide an immediate two charges, allowing Rennac to potentially charge up his AoE Special entirely by himself with Time’s Pulse and Quickened Pulse — no setup or outside assistance needed.
  • Alternatively, Barbed Shuriken provides a permanent cut to Rennac’s cooldown which, while slightly weaker than the upfront two charges granted by Quick Dagger, means that Rennac can forego the use of Flashing/Heavy Blade for stronger damage boosts or still use them to break through Guard effects.
  • Pumpkin-a-Box merits consideration purely for the visible Attack augmentation it imparts, as it’s important to consider that the damage calculation for AoE Specials involves visible stats only.
• His weapon choice is ultimately up to personal preference, though, and the same goes for the selection of a specific Blazing AoE Special as they all have the identical damage modifier and vary only in range. Blazing Wind and Blazing Light have the most generally useful layouts, though. 
• For his A skill, if foregoing Flashing Blade 4 or Heavy Blade 4 (due to having it equipped as a Sacred Seal or not at all in Barbed Shuriken sets), Life and Death is ideal as any sources of visible Attack prove quite useful due to the way AoE Special damage is calculated. This does come with a hefty five-point reduction to his defenses though, so Fury is another candidate if this is undesired.
• Time’s Pulse is a good C skill that reduces the amount of setup required to begin looping Rennac’s Special, though its scarcity means that more accessible options like Savage Blow are always welcome if unavailable. Beyond the aforementioned Flashing Blade and Heavy Blade, his Sacred Seal options branch out into further boosts to his visible Attack, Hardy Bearing to work around Vantage units, and Quickened Pulse.

Weapon: Broadleaf Fan+ (+ATK) 

Assist: Positional Assist  / Flexible

Special: Miracle / Glimmer 

Passive A: Close Foil / Close Counter / Atk/Spd Solo

Passive B: Vantage

Passive C: Smoke Skills / Flexible

Sacred Seal: Heavy Blade / Atk/Spd Solo / Brazen Atk/Spd / Fierce Stance

• His good base Attack and access to the notorious Broadleaf Fan makes a Vantage sweeper setup a decent alternative option for those who want to switch up his playstyle, though do note that this is admittedly a little outdated in the higher echelons of Aether Raids Offense — so take caution in how much you wish to rely on the traditional approach to this build. A +ATK IV is ideal given Rennac’s focus will be on maximizing his damage to consistently OHKO incoming foes in the Enemy Phase. 
• Pairing an Attack-refined Broadleaf — yet another great inheritable that directly adds to his raw damage based on the number of debuffs on his foe — with Vantage and an ability that enables counterattacks regardless of distance composes the core of this set; upon losing sufficient HP, this helps him cleanly sweep through incoming enemy forces. 
  • However, since the advent of Near Save does mean that Rennac could potentially forego worrying about melee threats altogether with the help of a properly-equipped armor ally, he could just retain his base Atk/Spd Solo to focus strictly on increasing his damage against ranged opponents. 
• Rennac’s Special of choice here primarily boils down to whether you prefer increased damage or some safety in his playstyle. For the former, low cooldown options like Glimmer are preferred to quickly unleash them. Otherwise, Rennac can equip Miracle as a last ditch "get-out-of-jail-free" option since even with Vantage, taking damage isn’t always avoidable; this should be paired with the Heavy Blade Sacred Seal to access it quickly. 
• Atk Smoke or Spd Smoke are options for enhanced damage via Broadleaf Fan in either his C Skill, Sacred Seal slot, or both, though Pulse Smoke is a nifty defensive alternative to somewhat deter enemy offensive pressure through slowed Specials. If Attack and Speed debuffs are already being readily applied through external means, though, Joint Drives are always a safe back-up option for free stats.
• If not using Atk or Spd Smoke, the Heavy Blade Sacred Seal helps Rennac charge his Special faster and remains particularly potent when paired with Miracle, as this helps him charge it up with much less setup and have it ready when he’ll actually need it.