...What is that first gun listed...? o-o You should probably censor it, since its spoilurz.

The Disintegration ray can provide you with a near guaranteed kill by cutting the enemy defense of a singular target or by holding back monsters in a narrow hallway.
For the single enemy it is best to use the ray on high priority slow/immobile targets (Lumbers and turret style monsters) after you fire the ray it is best to capitalize on the defense drop with a powerful sword combo.
For the hallway it is best to fire in with an unassisted (Auto target off) 5 star alchemer shots (deep in to get the most with bounces), Antigua spam, or just let your teammates tear up anything with a debuff mark.

The Violent heart attack is only good with weapons that provide such spread damage that monster deaths chain together, most of these weapons however are bombs and even then most bombers would rather have a Defense buff from the Iron Heart attack.
As a swordsman you can drop the Iron heart attack anytime you want because you should be able to kill at least a few monsters before it fades (as the heals you get should allow you to play a bit more aggressive), as a gunner however you should try to bring the all the monster's HP down together rather than focusing on a single target (unless we are talking high danger monsters like rocket puppies) that way you can drop the Heart attack once all the monsters are at a low enough HP so you can kill more.

The Valkyrian Aura is considered the best ultimate shield as it Maxes CTR and provides cover to you and teammates.
Unfortunately most teammates ignore the aura and would rather trust their own shields (which is why no one chooses the other ultimate).
This Aura allows the swordsman to go on a short rampage without fear of damage and allows a gunner to get out of tight situations. This aura has little use to bombers as most rely on getting Max CTR anyway with their armor, but this aura does allow someone (swordsman or gunner) with an extra slot to set up a few Vaporizer bombs while under the shield.

Well, Gran Faust and Sentenza are pretty useless in FSC. Other than those, your loadouts are good for FSC, but they completely abandon your support idea.

If you want to return to the support idea, but still be effective in FSC, then definitely consider DA, Triglav, Plague Needle, Storm Driver, vortex bombs, Voltaic Tempest. Maybe consider Hail Driver, Shivermist Buster, Stagger Storm, Venom Veiler (I've never used it in FSC).

Dazzling vs Disintregation Ray
Defense Down > Extra damage against Fiends and Undeads in term of additional damage

Violent vs Iron Heart Attack
Violent damage is bugged. The explosion does negligible damage.

Valkyrian vs Seraphic
Can't bypass max CTR, however in theory, you could buff your friends CTR. But they most likely avoid your aura and the aura won't last long enough when sharing. Seraphic alone is kinda meh. Sure shield regen sounds great but it wouldn't get you that far. Shield need to start regen (which is few moments after you stop getting hit) to notice the buff, and also not factoring if you share the aura with other players. I just hate how guardian ld shield has much better function than angelic aura. >__>

as Holy-Nightmare said, CTR buff is "for" your friends.
DA is one of the good charge attack weapon, btw. Well, there's bunch of weapons that charge outweighs the damage significantly than regular combo.

Well, I have nothing more to say.

For the Swordsmen Loadout, the Damage bonus stacks up to +8, which is already past max. Swift Steps II or Quick Strike II would be a better choice for the Sprite Perk. The Charges on the Antigua line weapons are considerably bad. It would be better to prioritize in ASI, or switching to a more Charge-Orientated weapon.

Most of the Seraphynx's abilities are rather close range. I think going with swords would be better. With all the buffs going towards swords in your loadout, it would probably be better to switch out the Argent Peacemaker with another sword.

I don't think any of those points are wrong, on their own. I'm trying to consider the "Support" aspect, though.

I said ASI instead of Damage because his Gunning Loadout already had maximum damage increase. An issue with the charge is that it knocks enemies to the side, spliting the crowd in half. Messes with others who could get multiple hits off of the close enemies. And it's rather slow to complete, leaving you open. Support characters shouldn't be the first to die, I think. A charge every now and then could work, but constant use would probably be detrimental to the team.

The Seraphynx's supportive abilities only really help at a closer range. Hanging back and sniping separates the team when the Aura is used, and it delays use of the Beam. If you only back up to use to charge, I guess it works? I don't know. The Aura and Heart Attack are very tank-y abilities, so I don't see much reason to back up and snipe.

At this point, have we completely abandoned the original post's concept of a support player using a seraphynx? Recent advice seems to be turning the original poster into another Brandish-Chaos offensive powerhouse.

Chaos is mentioned in post #11, if you were having trouble finding it.

Okay, Holy-Nightmare. I wasn't trying to attack you. The thread just seemed to be veering away from its special purpose, toward where all other Arsenal threads go...

By the way, it's not clear that the original poster is reading the thread anymore.

While that's true for damage buffs (and possibly speed buffs), the CTR buff will just instantly take you to max CTR, regardless of your previous CTR.

You wouldn't see me play much without my Seraphynx otherwise.