I've found that if your first art can be used to multi-hit set him up, so that your second art can be the spammed one to destroy him (such as my forcefield/parabola beam combo with Precis; I recently beat rd 50 with her *fist pumping in the air*). Multi hit attacks for the fighters can help. As for the mages, yes, the bunny shoes are mandatory, george :). Without the bunny shoes my mages get run down and beaten senseless; it's really sad for them.
Precis can't equip the cheap armor so that's the reason I never use her late game and most of the time when I "created" forcefield to use its worthless because its at the time I could fight Iselia Queen/Final boss limiter off.
Ripper Blast is good, but Dragon Howl's better (AKA the best). They'd probably work well together in a Link Combo as Dragon Howl, then Ripper Blast, but honestly, Dragon Howl is so spammable, I don't see the need for a Link Combo once you've got it. I actually tend to use Energy Sword (use it a lot and it gets pretty damn good) and Dragon Howl in the arena. If you're really having trouble, spam Dragon Howl 'til an enemy is stunned, then wail away on him with the Eternal Sphere.
Edit: I'm also surprised Vegh waited until page 2 to launch into his Bloody Armor schpiel. It's a new record.
I like ripper blast's half circle arc and range (from long range). Dragon Howl takes "too long" to execute against some of the higher round enemies like the Phantom Phoenix, Lv99 Thieving Scum, and Hell Savant.
Well without +100% hit rate weapons and a Bloody Armored Claude I had Rock Explosion connect against the Hell Servent and Dragon Roar get blocked 100% of the time.
That and with the cheap armor since I had to use Sword of Life to restore HP Rock Explosion drains less MP per use then Dragon Roar.
You have got to have the worst luck ever. From all of your posts I've read, your characters' guts doesn't activate, and you get blocked 100% (are you on Universe mode?). My Claude's attacks only got blocked about 40%+ of the time. And guts activated at least 3 times per those fights (for lowering damage to self/survive with 1 hp) and many times for "critical" hits..
Well in the case of hits being blocked for Hell Servent I had that happen on earth mode when using Ripper Blast/dragon roar and never had guts kick in when I had its master attack do 9999 damage in 1 hit and the blocked hits I had that happen even with every battle skill maxed out to level 10.
But I could fight Iselia Queen earth mode level 255 (for a maxed 255% guts) still had every one of her physical hits do 9999 each and still had the RNG hate me by having guts never kick in at all.
That's why against IQ/Limiter off final boss I had to use 4x Bloody Armors for earth mode.
On Universe without Marvel Swords equipped I had most physical hits and KM's always get blocked as soon as the game starts for the entire game that's why I can't use the Eternal Sphere as a best weapon for Universe mode.
But then again the RNG hates me in every RPG I play for in battle use.
I also had Live Flayers/Level 99 Funn Thieves do 9999 per attack on earth mode and never had guts kick in either.
Well the bonus dungeon enemies floor 10 onwards hit so hard even with all the armors found their I took a 9999 damage Live Flayers missile 5 seconds into the fight and never had guts kick in for a easy game over.
So I had to use the bloody Armor I had the Master Attack Hell Servant kill Claude instantly as soon as it connects even on earth mode at levels over 100.