You keep doing that to older DnD players too, except you drop hints that the enemies are in a cult that has been giving them power and when the wizard does fireball them, the wizard gets hit by a dozen hellish rebukes from all the young warlocks they just hit.
Does hellish rebuke activate after though? Cause if the caster is likely to be killed I would take that bet
It does, but giving a warlock enough dex (which considering they dont get heavy armor prof is reasonable) to pass a dex save occasionally and like 18 hp is all you would need for this to be a major issue.
But then you also give them terrain that would allow a clever wizard to position themself such that they can see the epicenter of the fireball without having line of sight to the targets themselves
