Cloudstone Curio | Hornet Queen | Mana Echoes (and one other card)

$the front side of Energy Refractor$

Cards

({4} magic symbol) ({G} magic symbol) ({G} magic symbol) ({G} magic symbol) available.

Cast
Hornet Queen by paying ({4} magic symbol) ({G} magic symbol) ({G} magic symbol) ({G} magic symbol) .
When
Hornet Queen enters the battlefield, it,
Cloudstone Curio, and
Mana Echoes trigger.
Resolve the
Cloudstone Curio trigger, returning nothing to your hand from the battlefield.
Resolve the
Hornet Queen trigger, creating four 1/1 Insect creature tokens.
When the Insects enter the battlefield,
Mana Echoes and
Cloudstone Curio each trigger four times.
Resolve the first
Cloudstone Curio trigger, returning
Hornet Queen from the battlefield to your hand.
Resolve all remaining
Cloudstone Curio triggers, returning nothing to your hand from the battlefield.
Resolve all
Mana Echoes triggers, adding ({5} magic symbol) for each Insect you control.
Activate
Energy Refractor three times by paying ({6} magic symbol) , adding ({G} magic symbol) ({G} magic symbol) ({G} magic symbol) .
Repeat.

This combo has been estimated to be Exhibition (Bracket 1+).