maybe the hp scaling can be tuned down a bit for party play - I tried a few times playing this in a party (up to lvl 30) and most of times I got significantly worse result than playing solo
Converse with fellow players
the 15-star weapon/12-star unit give away lasts until Dec 22 - you simply need to run the Limited Quest (any difficulty) 9 times to receive a pre-affixed 6-slot Ofz unit set, should be a big upgrade over the Brissa set.
Another option is buy Starquake unit from player market (cost ~1 mil each on ship 2), upgrade them to Trailblazer (each cost 50 currency from Malevolent Void UQ), and affix them yourself with budget 5-slot augments (cost 2~3 mil each)
for rings, you'll definitely want Technique Charge Parry L ring, not sure about the rest since I don't play force.
The luminmech one will sort itself out in around a week when the Armada of Annihilation UQs appear, I hear.
Hopefully someone will discover a drop source for Support Roll soon. Doesn't seem like the christmas UQ can drop any but that could be a blessing since it'd only be temporary if it was just that.
Support Roll has been farmable since the beginning -> keep deleting/creating summoner alt and grind Pietro, should take around an hour, but mind numbingly dull
I think by the time Sega release an easy way to get Support Rolls, we will have S6 Wise Skill already which makes those rolls kind of pointless, so for now it's better to work on your max PP instead (100% crit requires 245 PP with 1 roll, 295 PP with 0 rolls)
Can't do that if three of his attacks can hit the whole room at once regardless of where you are.
Also the ring attacks he does also affect all party members, this includes the pets. Unlike players in the air, the boss has a 100% accuracy on pets, to balance summoner.
we summoners can also dodge you know the ring hits pet for very little damage at current depth so summoner is definitely easy mode for this fight. I heard at some point boss will start one-shotting pets, no idea how summoners can get past that ...