Herigast, Erupting Nullkite | Cloudstone Curio | Flameshadow Conjuring

(and two other cards)

Nonartifact, Nonlegendary Creature with a Generic Mana Cost

You have enough mana to cast the creature with a generic mana cost either for its mana cost or for its emerge cost.

Cast the creature with a generic mana cost by paying its mana cost or emerge cost.
Birgi triggers, adding ({R} magic symbol) .
When the creature enters the battlefield,
Cloudstone Curio and
Flameshadow Conjuring trigger.
Resolve the
Cloudstone Curio trigger, choosing to return nothing to your hand.
Resolve the
Flameshadow Conjuring trigger, choosing to pay ({R} magic symbol) to create a token copy of the generic mana cost creature.
When the creature token enters the battlefield,
Cloudstone Curio triggers, returning the nontoken generic mana cost creature from the battlefield to your hand.
Cast the generic mana cost creature for its emerge cost by sacrificing the creature token created in step 5, and by paying ({0} magic symbol) as the token will have the same mana value.
Repeat from step 2.