Open world and solo story build
Phantasm builds can be nice for these – especially with duelists or warlocks who can keep shooting and not get destroyed by AoE around the mobs.
One point from the latest living story, there’s a fight where you have to attack a boss in the middle of a large circular field. My phantasms were useless there. The protective aura you get doesn’t apply to them, so they died in an instant.