MTG Salvation

9/20/2016 The first ability counts the spell that caused it to trigger plus any other spells you cast earlier in the turn.

9/20/2016 The first ability counts spells you cast earlier in the turn even if you didn’t control Aetherflux Reservoir as you cast them, and even if those spells were countered.

9/20/2016 The number of spells you’ve cast is counted only as Aetherflux Reservoir’s triggered ability resolves. For example, if you cast a spell, then respond to the triggered ability with a second spell, you’ll gain 4 life total.

9/20/2016 Aetherflux Reservoir’s first ability doesn’t trigger when you cast Aetherflux Reservoir itself.