Keeping it brief, think up of combinations of magics/weapons/styles while considering awakening benefits.
Can be anything really, even things that aren’t out or confirmed (such as lost spells that may or may not be added).
Examples:
Flare infused arcanium blunderbuss for multiple stacks of DOT
Zones + synergy magic (assuming zones inflict status or can maintain it: Water zone + lightning attacks)
Edit -
It can also be mono magics with buff stacking:
Light mode (attack speed) + attack speed accessories + a blast ultimate with 20 blasts