If you have two explosive arrow setups, one with elemental focus (EF) and another without, will the EF setup contribute to an explosion's ignite damage if the one without EF is the first to expode?
Ignite Damage is part of damage calcualtion. Each arrow calculates it's own damage with it's own stats. They are only summed after damage is calculated. An arrow with EF cannot ignite, so will calcuiate 0 ignite damage, and that's what it wil contribute to ignite damage when the individually calculated damages are summed.