The damage of the Tephra Bomb passive is only calculated from one part. It should take both passives into account, from weapon and amulet, or it takes an usefull spot away on alot of items.

steps to reproduce:

• place a volcano with the lavamancer who has the Tephra Bomb passive on the weapon and amulet
• wait till the big rock is attacking something
• notice how the damage of the big rock is only taking one of the 2 passives into account

Expected result:

The big rock from the passive Tephra Bomb does the combined damage of both passives. Or the passives is only available on weapon or amulet.