Saheeli, the Sun's Brilliance | Mana Echoes | Deceiver Exarch

(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
Deceiver Exarch.

Activate
Saheeli by paying ({U} magic symbol) ({R} magic symbol) and tapping it, creating a token copy of
Deceiver Exarch with haste.
When the token
Deceiver Exarch enters the battlefield, it and
Mana Echoes trigger.
Resolve the
Deceiver Exarch trigger, untapping
Saheeli.
Holding priority, if you control less than four creatures that share a creature type with
Deceiver Exarch, 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
Deceiver Exarch for each trigger resolved this way.
Activate
Urn of Godfire twice by paying ({4} magic symbol) , adding ({U} magic symbol) ({R} magic symbol) .
Repeat.