Does Battlefield Void Gate (+1 damage for abilities/spells) increase Volibear's 5 split damage to 6 total, or does it add +1 to each individual target hit?

Ruling: Battlefield Void Gate adds +1 to the total damage, making Volibear's ability deal 6 damage split among enemy units, not +1 to each target.

Nuances:

• The +1 damage is applied to the total amount being split, not to each individual target that receives damage from the split