FF6 Ultimates are out. First fight is a three wave gauntlet of mobs that have low health, but hit very hard. Summoners are great (most are weak to water and lightning).
For the U+ cid mission against Guardian, I went for a pure magic team with Ashe's BSB as a roaming warrior, which worked out well (helps I have great magic synergy in FF6... and no physical synergy at all). He counters every physical hit, so Mog as a breaker using dances is helpful so that you never trigger any counters. If anyone wants to add me as a friend, I currently have my RW set as Ashe with her BSB (geared for FF6 synergy, I think like 470 magic and +20% thunder damage). My friend code is: KtTW
Team I used was:
Celes -- Thundaja, Draw Fire -- Default SB (this was actually useful, it's a stacking res buff)
Terra -- Ixion, Ramuh -- RW Ashe's BSB
Kefka -- Chain Thundaja, Thundaga -- Mage Shout SB, then RW Ashe's BSB
Mog -- Magic Break Dance, Fullbreak Dance -- Shared Shellga SB
Relm -- Curaja, Protectga -- Medica SB
RW: Dusk's Decree (Ashe BSB)
The Kefka U++ wasn't bad, even with zero physical synergy, but it took a few reloads because of the RNG on his counter-confuse. Two attempts in a row he kept confusing my healer back to back, which forced a reload. Once he decided to only confuse the not so important dps, it was a clean kill. I brought enough stacking magical breaks to have him completely broken to the cap, which of course neutered his damage dealing abilities to the point that his confuse was the only real threat. Maybe I should have brought confuse resist accessories (if they even exist, didn't check). My U++ team was:
Cecil -- Banishing Strike, Saint's Cross -- Holy Force BSB
Vaan -- Lifesiphon, Thief's Revenge -- Ark Blast BSB (-40% mag/def)
Agrias -- Lifesiphon, Shellga -- Cleansing Strike SB (-50% mag/atk)
Ramza -- Power Breakdown, Fullbreak -- Unsung Hero BSB
Relm -- Curaja, Diaga (should have been esuna) -- Medica SB
RW: Shout
Videos of my kills:
Ultimate Gauntlet
Cid Mission Ultimate+ Guardian
Kefka Ultimate++
Edit: Yimmien, Garland's BSB is ranked as one of the weaker BSBs... and overall as you mention, his skillset isn't that special, and as a character he has poor stats. If you have other units, it may be time to show him the bench! Darkness is mostly a magic school for now, though we're getting some physical skills in the darkness category soon.