Bifrost monsters have over 90k HP. How on earth are you getting RC to do over 30k per hit?
Love your question and would be glad to answer it(Would love to reveal a few secrets) xD.......but
+12 Violent Durga,+12 Nab/Sapha Cloth(Depending on what purpose im using them for,mobbing or autoattacking)FS5/Crit +/% Enchants,+12 Mystic HBP/+12 Nab Hood,+12 Nab/Sapha Shoes,2 RT or 2x RWC Rings.
This is my current gear setup right now,of course exchanging and swapping with other equips,depending on the situation.
And since you dont need that many reducts in pvm nowadays,I can safely wear these against bifrost monsters,but usually,I kill everything from Little Fatum to Luciola Vespa with 3 RC counters doing about 25-28k a spin and this is without edp.I have a few more secrets ofc to inc. my damage up this far or even farther without damage enhancers,but you'd have to pm me for that.....
One thing I wanna make clear though is that......I dont except casual players to have this kind of gear setup,but this is what I have and it works pretty well xD
P.S.-Usually takes 2 more counters to kill Angry Mantises and Poms.....xD