So Half-illithid warlock Tav + storm cleric Shadowheart + Minthara hits like a truck apparently. Everyone has initiative bonuses, so first turn Minthara hastes Tav, Tav casts black hole to cluster all enemies together, then Hunger of Hadar’s them, Shadowheart then calls an upcasted Call Lightning with divine strike and obliterates everything. You can delete half the health of almost all the enemies in the first round if you get lucky, and they all get severe movement penalties from the black hole and hunger of hadar. Plus Astarion multi-classed rouge/fighter/gloomstalker with action surge and crit bonuses can pick off like 4 enemies in the first round too. Then Minthara smites the survivors into oblivion.
Fun times.
Try pairing it with Minsc as a STR/DEX Hunter with the Punch Drunk Bastard, Titanstring Bow, and Gloves of Belligerent Skies. You get better than the equivalent of 6th lvl Call Lightning as an attack.
Also Ascending the Tadpole in Act 1 (Monastery) means you can Haste the damage (Minsc in my earlier example) rather than Tav as Black Hole will become a Bonus Action.
Okay I didn’t even know you could get that ability from the monastery, I swear the amount of stuff to find in this game is ridiculous. Also I really should use Minsc sometime, always get him too late to use him much. Next run I’ll get him before the other companion quests and bring him along to go smack some vampires.