The Porta Decumana
- See also: The Minstrel's Ballad: Ultima's Bane
The Porta Decumana
- Level
- 50 (Sync: 50)
- Item Level
- 42 (Sync: 60)
- Difficulty
- Normal
- Party size
- Light Party
4 man • 1
1 
2 
- Unsyncing
- Allowed
- Time limit
- 60 minutes
- Roulette
- Main Scenario
- Tomestones
100 - Req. quest
The Ultimate Weapon- Patch
- 6.1
“Making your way through the Praetorium, you sweep aside wave after wave of defenders before finally coming face-to-face with Gaius van Baelsar himself. Unable to overcome you by his own hands, the Black Wolf takes control of the Ultima Weapon and sets upon you once more. Do what you have come to do, and see that the magitek monstrosity never threatens Eorzea again.
— In-game description
The Porta Decumana is a level 50 trial introduced in patch 6.1 with Endwalker.
Guide
Ultima Weapon
During the beginning of the Ultima Weapon fight, you cannot harm the boss as it has a buff that reduces all damage to single digits. The healer should therefore be careful as the tank will be unable to hold aggro compared to that generated by any healing. After a short while, or a certain amount of damage (it is unclear), the boss will lose the buffs and can be dealt with as normal. The tank should 
Provoke as soon as this happens to establish a firm aggro lead.
Abilities
- Garuda is an narrow donut around the arena edge for moderate damage.
- Titan is an ring of circular AoEs around the arena edge, followed by four circle AoEs covering the center of the arena.
- Ifrit is an point-blank AoE centered in the arena.
- Ultima Weapon also has a line AoE, a point-blank AoE, and a raidwide.
Phase 2 also has:
- Magitek Bits spawn in pairs and target random players with cross-arena line AoEs for moderate damage.
- Periodically a gunship will crash on a proximity marker for high damage. Move away to mitigate this.
- Occasionally a large glowing ball shoots slowly from Ultima Weapon towards a marked player before exploding in a point-blank AoE.
- Ultima at low health, the boss disappears briefly before returning to start slow-casting the enrage attack.
