She is easy on a well balanced comp. Bring at least one caster for counterspell, and have enough AoE. Most people I see playing are not using any scrolls at all. A single ice storm and all of those mobs were knocked prone. You can also preload summons before going into the fight, or your martials can use void bulbs to suck in the enemies into a single spot and cleave them down.
I was running a suboptimal party comp of two moon druids with a wizard and cleric, and still not a single ally died.
By the way, with her assault, if you saved the Hyenas and severed their connection to the halfling cultist, and convince them you are a friend, they will join you for that fight.
