Feolthanos Exultant is the final boss in Final Fantasy XII: Revenant Wings, and the second-last form taken by Feolthanos. It is a monstrosity composed of three parts: Feolthanos Medi, the torso, Feolthanos Dex, the right arm, and Feolthanos Sinis, the left arm. All three are classified as Group Leaders, but only Feolthanos Medi must be felled to win. If the game progress is 100% completion, Exultant's level raises to 99, including his two supports, Dex and Sinis.
The lord of the aegyl, bound by the shackles of eternity.
Left hand of the Eternal that metes out his judgment.
Right hand of the Eternal that heralds total annihilation.
The player's party of five group leaders starts out in the southwestern section of the map, flanked by two allied Summoning Gates. Feolthanos Exultant lies to the northeast: Medi is straight ahead, at the end of a large staircase, while Dex is to Medi's right and Sinis to Medi's left. Several battalions of Wing Wraiths guard each part.
Each component of Feolthanos Eternal has the ability to summon four more Wing Wraiths at certain intervals. They do this via three circles of light that lie near to each part. Once each section of Feolthanos Exultant is destroyed, Wing Wraiths may no longer be summoned from that part. These summoning circles are not Summoning Gates; that is, the allied party cannot attempt to "capture" the source of Wing Wraiths.
Feolthanos Dex should be the first target. Its attack, Judgement, hits all units for heavy damage no matter where they are on the field. Thankfully, Dex will only use this attack at a rate of approximately once every 30 - 40 seconds.
Next up is Sinis. Its attack, Condemnation, deals heavy area damage to all units around it. The player's Melee and Flying units are the only ones who need to worry about this, but approaching Wing Wraiths will attack the party's Healing and Ranged units from behind.
Medi is last. The units can climb the staircase and whittle it down to about 50% of its total HP without any retaliation, but for the constant spawning of Wing Wraiths. Once Medi reaches this halfway point, Bahamut is summoned. The party must try to defeat the scion quickly before it can cast Mega Flare.
Medi's passiveness ends at this point. He begins using the Faithless Cry at regular intervals, at a greater frequency than Dex's Judgement. Faithless Cry sends a destructive beam of energy straight outwards, engulfing the entire staircase and everything in front of it. This attack, combined with the increased rate of Wing Wraith summoning, makes Medi difficult to approach. Faithless Cry is used slightly more often than summoning Wing Wraiths (for each five Faithless Cries there is one second difference).
The player should begin by summoning more Rank II Espers onto the field with the Rank III Esper, and use them to attack Feolthanos Dex and wipe out any Wing Wraiths on the way. It is important to destroy this arm first, as Judgement can put the party in trouble. After the Arm is destroyed, the summoning gate for Wing Wraiths is destroyed along with it.
Afterward, the party should regroup back in front of Medi moving on to the left arm, called Sinis. It will use Condemnation every now and then, but it is only a problem for units up close, such as Vaan and Filo. Wing Wraiths will try and hit the party's Ranged units from behind, and if that occurs, the party should turn their attention to them and wipe them out before attacking Sinis again. When Sinis falls another summoning gate for Wing Wraiths will fade away.
The party can again regroup and heal in the center. The Wing Wraiths will only attack from the front. Medi will not use Faithless Cry until its health is lowered to 50%. It is best not to use Quickenings as they will be needed later. Once Medi is down to 50% Bahamut will appear, and Medi will start sending a massive beam called Faithless Cry. Everyone should run down the stairs and off to the side to avoid this, and leave the party's Rank III Esper, and some Rank II Espers, to distract Bahamut. One should keep sending Espers until Bahamut is dead, then cast stat enhancing moves on the player units before going for the final charge. Medi will still use Faithless Cry frequently, however, it is not so bad as Bahamut is dead, and all that are left are some Wing Wraiths. Now the party can use all of their Quickenings.
If Faithless Cry is too much to deal with, the party can also find a spot from the right side of the podium to attack the core. Balthier and Ashe can attack consistently while the ranged abilities from Kytes, Lluyd, Basch and Penelo can also. The others can shield the duo by fighting the Wing Wraiths and Bahamut. Whittling down the core's HP with only leaders takes time, but the party is shielded from Faithless Cry.
A good tip is to summon the Rank III Yarhi under Basch while he uses Cover and let the Rank III Yarhi attack Feolthanos alone while Basch, together with all healing units, stands close to a Summoning Gate, so Basch gets his damage healed. His Quickening can also be used to make his group temporarily invincible. Also, if one does not let the Rank III Yarhi attack the Wing Wraiths, they can do much damage to raise the Quickening frequency, and when there are around twenty Wing Wraiths, no more will be summoned.
"Exultant" is an English word that means "triumphant", derived from the Latin word exsulto "to rejoice exceedingly".
Medi refers to the Latin word Medius, which means "middle, midmost, central".
Dex and Sinis refer to the Latin words Dexter and Sinister, which contextually mean "right" and "left" respectively.