Muri, Voice of the Reef

Whenever you cast a noncreature spell, put a
cadence counter on Muri.
Kraken, Leviathan, Octopus and Serpent spells
you cast cost {1} less to cast for each cadence
counter on Muri.
Whenever you cast a Kraken, Leviathan,
Octopus or Serpent spell, you may remove a
cadence counter from Muri. When you do, that
spell gains cascade.