Combining Spell Effects

The effects of different spells add together while their durations overlap. In contrast, the effects of the same spell cast multiple times don't combine. Instead, the most potent effect-such as the highest bonus-from those castings applies while their durations overlap. The most recent effect applies if the castings are equally potent and their durations overlap. For example, if two Clerics cast Bless on the same target, that target gains the spell's benefit only once; the target doesn't receive two bonus dice. But if the durations of the spells overlap, the effect continues until the duration of the second Bless ends.