Aether Flow

Splice onto Arcane {p/r}{p/u} (As you cast an Arcane spell, you may reveal this card from your hand and
pay its splice cost. If you do, add this card's effects to that spell.)
You get {e}{e}{e}{e} (four energy counters), then
pay any amount of {e}. For each {e}{e} (two energy) you pay add 1 mana of any color to your mana pool.