For the Ancient Ruins, I followed the advice of F95 members (thanks for that advice) order of formation I used.
Simon, Hilstara, Carina and Robin. I equiped all with 'barrier' pins
With Simon I equipped him with all the best I either bought or found as you play out the game.
Hilstara, Heavy Sheild, Hilstara's Helm, Mammoth Armor
Carina, I equipped with the best magic items I could buy or found during game play.
Robin, was also equipped with the best I could find.
Use Hilstara as a human sheild/main target, then use 'guard' when the turn cycles back to her turn to attack. FOr healing I used Carina on every turn, I also had to Simon for healing potions, and sacred revival potions (to keep Hilstara alive).
The Yellow Knight can be heavily hit with Robin magic (flame), THe Blue one can also be hit heavily with Robins magic (lighting). I took out the Yellow one then focused on the Green, then finished off the Blue one. The Green Knight is resistant to magic, tho you can still use it and get about 2,000 hit to his HP, I used Simon's Precise Strike which varies from 1,200 to 2,000 hit.
NOtE I could be wrong about which magic attacks to use, but you should be able to find out quickly which ones can be used against the Yellow and Blue knight! ANd this time around this fight/battle went very smoothly, there were a few times when it looked liked I was getting into some trouble, but it wasn't as intense as the 20 previous attempts where I failed.