Fallen Muarim

Weapon: Wild Tiger Fang

Assist: Positional Assist

Special: Noontime / Glimmer / Moonbow

Passive A: Atk/Spd Solo / Atk/Spd Push 4 / Atk/Spd Ideal / Atk/Spd Unity / Kestrel Stance / Distant Pressure / Distant Dart / Surge Sparrow

Passive B: Null Follow-Up

Passive C: Spd Smoke 4 / Even Tempest / Even Atk Wave / Joint Drive Spd

Sacred Seal: Darting Breath / Atk/Spd Solo / Spd/Def Solo / Spd/Res Solo / Mystic Boost

• In this build, we focus on bringing together skills that improve Muarim's damage and longevity in both enemy and player phase. Building on his high Speed is a surefire way of doing this as it serves to minimize natural follow-ups against him and maximize his chances of following up against enemies himself.
• With Wild Tiger Fang effectively already providing a built-in form of enemy bonus negation (making Lull skills redundant) and beasts being unable to access Dodge skills, it all narrows down to Null Follow-Up essentially being Muarim's best generalist B-slot. Adding Null Follow-Up to Muarim's already-expansive list of combat effects makes him an all-around fantastic fighter, especially given the number of units nowadays reliant on follow-up manipulation skills. 
• To prime Muarim's fighting for any situation, an A and/or Sacred Seal slot that provides Spd and (preferably) additional Atk in both phases is the way to go. Atk/Spd Solo and Push 4 are fairly common inheritance choices for this. 
  • That said, some skills listed work in specific phases but come with effects that are worth the trade-off. 
    • Distant Dart, for instance, allows Muarim to counterattack ranged enemies and overall opens the list of things he can counterattack significantly. 
    • Surge Sparrow's offensive boosts and on-Special healing triggers only if Muarim initiates combat, but considering how much punishment Muarim takes between Wild Tiger Fang's recoil as well as repeated enemy assault, it's definitely worth playing smart for the opportunity to heal it all back.
    • Darting Breath kicks a chosen 2 CD Special into full-charged gear instantly after tanking any incoming attack in the enemy phase. Considering all the Special perks that come with Wild Tiger Fang (i.e. Guard effect negation and +7 damage on all Special triggers), this one is worth seriously taking unless you're able to provide some outsourced form of it (such as Brave Lucina's Geirskögul or Thórr's Worldbreaker).
    • Mystic Boost's 6 HP recovery after combat completely offsets the 5 recoil damage from Wild Tiger Fang and generally provides longevity if there are no other sources of healing on your team.
• The choice of Muarim's Special comes down to a 2 CD Special as the lack of Slaying effect (CD -1) typically bogs down more interesting choices.
  • Noontime promotes longevity, and even though it only provides healing upon activation, Muarim still gains a bit of burst damage +7 thanks to the transformed perks of his weapon. 
  • The age-old debate between Glimmer and Moonbow strikes again for a potential short-charged damaging Special. More than likely, Muarim's high damage output makes Glimmer a pretty reliable choice against all but exceptionally high-Def enemies, a situation in which case you can opt for Moonbow instead just to be safe.
• Muarim's C slot is fairly relevant to the optimization and playstyle of this build:
  • Fortunately, in the same update Muarim comes in, Spd-based damage reduction is now available to beast units through Spd Smoke 4. Not only does this grant Muarim significantly more longevity by filtering stray hits from slower enemies, but Spd Smoke 4 also greatly swings Spd comparisons greatly in buffing Muarim's Speed while debilitating enemies around him. This does, however, require Muarim to enter combat before the effect activates, so be sure to start battles carefully. 
  • Even Tempest is another C skill Muarim can run to increase his movement and initiation options, and it's even synchronized to Muarim's turn-based transformation. 
  • Lacking these entirely, you can run Muarim's more tame, evenly-timed default C skill for a self-buff, Even Atk Wave. Else, a relevant Joint Drive is always appreciated for mutual stats increases between Muarim and his allies.

Weapon: Wild Tiger Fang

Assist: Positional Assist

Special: Galeforce

Passive A: Swift Sparrow 3 / Atk/Spd Push 4 / Fury 4 / Surge Sparrow / Flashing Blade

Passive B: Wings of Mercy / Null Follow-Up / Hit and Run

Passive C: Time's Pulse / Even Tempest

Sacred Seal: Flashing Blade / Heavy Blade / Blade Session / Swift Sparrow

• Muarim's access to certain infantry skills as well as high overall offenses and Wild Tiger Fang's various favorable effects (especially the ability to ignore Guard) makes Galeforce a pretty potent overall choice for him. The extra action granted by this Special gives him another opportunity to close in on another kill or escape to a favorable position, making up for a lack of Canto movement on him.
• Ideally, Muarim would want to trigger Galeforce in a single sitting. Doing so, as always, is a bit difficult with a 5 CD Special, so we account for this with the standard Galeforce build fixings:
  • Heavy or Flashing Blade accelerates cooldown charging on every hit assuming Muarim abides by their stat comparison conditions. Due to Muarim's high Spd and the fact that Atk checks are more difficult to beat on average, Flashing Blade is slightly preferred. Unless you have specialized, outsourced ways to achieve accelerated charging (like Thórr's Worldbreaker), these will be required in either the A or Sacred Seal slot.
  • Time's Pulse further reduces the amount of work needed to get Galeforce going by cutting it down by -1. With it, Muarim will never require a counterattack as long as Flashing or Heavy Blade is active in two hits. Of course, this can be substituted with external support like Infantry Pulse, and Muarim can instead consider Even Tempest to increase his threat range on transformed turns.
  • Of course, Muarim needs to hit hard and beat his Blade skill checks, so his remaining passive A or Sacred Seal should be occupied with an initiation-friendly Atk/Spd boosting skill. Notably, the recoil of Fury combined with that of Wild Tiger Fang may give allies with Wings of Mercy the opportunity to teleport to him when he is at lower HP. Otherwise, conventional choices like Swift Sparrow or Atk/Spd Push will do just as well.  
• On typical Galeforce compositions in Aether Raids Offense, Wings of Mercy allows Muarim to teleport from long distances to a damaged ally (typically a specialized Wings of Mercy beacon) and overcome his otherwise pretty so-so movement. 
  • In other settings, Null Follow-Up and Hit-and-Run are more generalized choices, with the former preventing hiccups from enemies with follow-up prevention skills, and the latter providing an additional space of stepback after Galeforce activation. 

Weapon: Wild Tiger Fang

Assist: Positional Assist

Special: Glimmer / Moonbow

Passive A: Fury / Atk/Spd Push / Distant Storm / Other Atk-based Push 4 skills

Passive B: Wrath / Desperation

Passive C: Time's Pulse / Even Atk Wave / Even Tempest

Sacred Seal: Fury 3 / Atk/Spd Solo / Steady Breath

• Muarim can build the recoil and +7 true damage on Special trigger from Wild Tiger Fang combined with the various Special effects from his default B passive, Wrath. Together with other recoil-building passives such as Fury, various Push skills, and/or Distant Storm, these skills make for an effective low-HP, Wrath-powered Special spamming build. Under optimal conditions, Muarim is dealing an additional +17 damage on whichever Special he chooses charged every turn.
• Alternatively, you can run Desperation as a method of reliable general gameplay sweeping. With it, Muarim gains extra safety in attacking with his follow-up attack happening before the enemy can make their move. 
• We've pretty much already covered the point and meat of the build. Of course, we can't have a Special spamming nuke without a Special to talk about. Hence and due to Muarim's lack of Special cooldown acceleration in his weapon — practically pushing him to run 2 CD Specials for low trigger consistency — this boils down to pretty two conventional choices: 
  • Glimmer typically has the higher damage potential, firing pretty well against the majority of enemies that don't have an obscene amount of Defense. 
  • Moonbow gets better results against higher Def enemies if those are a particularly biting concern. 
• IF you're running the Wrath build, Time's Pulse is pretty much the one-and-only C, as it makes Muarim's chosen 2 CD Special even more ready to run at the start of every turn. Together with Wrath's cooldown charging, the Special in question should be fully charged. Outsourcing-wise, the only direct substitution to this is Ostia's Pulse. For Desperation builds, Time's Pulse is pretty optimal for quicker Specials but not entirely required. In that case, alternatively, you can lay back with Even Atk Wave as a doable budget option or Even Tempest for longer attack reach.  
• Steady Breath is worth mentioning as the Sacred Seal option so that Muarim can trigger his Special on every counterattack if engaging multiple enemies in one enemy phase, rather than waiting each turn for his Special to charge via Wrath and Time's Pulse. Else, it should be taken up by Fury or another offense-boosting skill.