Saheeli, the Sun's Brilliance | Mana Echoes | Gemstone Array

(and one other card)

Saheeli does not have summoning sickness.
({U} magic symbol) ({R} magic symbol) available, plus an additional ({U} magic symbol) ({R} magic symbol) if you control less than three creatures that share a creature type with
Sky Hussar.

Activate
Saheeli by paying ({U} magic symbol) ({R} magic symbol) and tapping it, creating a token copy of
Sky Hussar with haste.
When the token
Sky Hussar enters the battlefield, it and
Mana Echoes trigger.
Resolve the
Sky Hussar trigger, untapping all creatures you control.
Holding priority, if you control less than four creatures that share a creature type with
Sky Hussar, repeat steps 1 through 3 one additional time.
Resolve all
Mana Echoes triggers, adding ({C} magic symbol) for each creature you control that shares a creature type with
Sky Hussar for each trigger resolved this way.
Activate
Gemstone Array's first ability twice by paying ({4} magic symbol) , putting two charge counters on it.
Activate
Gemstone Array's second ability twice by removing two charge counters from it, adding ({U} magic symbol) ({R} magic symbol) .
Repeat.