Froggy, Spell Hopping

Whenever you cast an Instant spell, put a croak counter on target creature. Whenever a Frog enters the battlefield, double the number of croak counters on target creature. Remove a croak counter from target creature: Add 1 mana of any color. Spend this mana only to cast an Instant or Sorcery spell.{flavor}“The voices of my people give me power.”