Titan armor set, have a shield with 100% strike resistance (I had the Pruina Scutum) and I had the defenders ring equipped for extra measures.
Soon as you enter the fight. go to one corner and shield up, wait for them to basically corner you. The knight and Kings attacks will push you around, The trick is to wait for them to push you to the other side where all three are technically in the corner. Use the Dart Brand to cover ground quickly making it to the opposite side, the Judge floats and she will get to you faster then the other two, so take her out first as I did. The king and knight are easy as it just requires timing. Dodge and attack when the time is right.
Judge and King - Arcane works well.
Knight - Fire