|This build will utilize and build upon Loki's Gravity Ploy Weapon. Panic Ploy 3 has good synergy with her weapon to combo both Gravity and Panic Ploy for putting foes at a disadvantage.
A Slot: You can keep C Duel Infantry 3 equipped for +5 HP to help her ploy skills. Boost HP for ploy effectiveness anyway you can though, otherwise boost Attack for maximizing her offense. Real Simple.
B Slot: Dazzling Staff 3 is the obvious best choice for Loki for her staff but this skill is hard to obtain. Live to Serve 3 is good to ensure her HP stays high to activate her Ploy abilities. If you want something else, Wings of Mercy 3 can be helpful in general for support.
C Slot: Odd Atk Wave 3 can be used in general due its usefulness for +6 Atk buff. You can also give her Panic Ploy 3 here to combo with Gravity Ploy from Loki's weapon.
SSeal: These are flexible due to having both Panic Ploy and Live to Serve being available as a Sacred Seal to free up the B and C slot for other combinations.