The importance that Mestre Bimba gave to the "game" of capoeira is expressed by the requirement that the "graduated students" execute the game of Iúna as confirmation of their qualification as a capoeirista.
The Jogo de luna was a rituralise part of capoeira regional which mestre bimba incorporated for the graduate capoeirista to demonstrate his/her skills.
Iúna is a game of capoeira that accompanied the touch of berimbau , used to demarcate the levels hierarchy of teachers and learners ( disciples ). This game is only allowed to practitioners who are at least graduated from the teaching level in capoeira (Graduate), and is traditionally done without clapping, singing or any other instrument besides the berimbau, to enhance the solemnity of the occasion. However, in some places, especially in Angola's capoeira , other instruments can accompany the game. The touch of iúna (like the other touches) does not have an identified creator (just as there is no 'creator' of capoeira), but some capoeiristas attribute its creation to Mestre Bimba , as a way for graduate students to demonstrate their skills — such as jumps, pirouettes, frills, handstands, among others. During this game, the objectivity of the blows gives way to dexterity and elasticity of the movements , which become more elongated and choreographed. Mestre Bimba used to develop in this rhythm the so-called "despised-waist" or "waisted balloons", which consisted of a sequence of balloons (movements in which a player is thrown into the air and needs to fall standing up), generally required of the graduated student.
Iúna is an old viola guitar rhythm used in the sambas of the Recôncavo, Bahia. Bimba, himself an accomplished master of the viola de samba, brought iúna into capoeira as a rhythm on the berimbau. He said that was an imitation of the Iúna bird's song - of the male calling and the female responding. A medium-paced and graceful game, it is played traditionally by "formados" (graduated students) at the end of the roda. Iúna is characterized by an emphasis on florieo and beautiful movement around the roda, with little to no contact/fighting.
The term iúna originates from the abbreviated name of the bird “inhuma” or “anhuma”, from the family of Anhimidaes. These birds are from South America. Its mystic aura has become a symbol of Capoeira. This bird is said to be a mandingueiro. The term iúna may have originated from the Tupi language referring to water (i) and the color black (una); the kamichi or anhuma belongs to the same family as geese and ducks. It is similar to a guinea fowl -konken in Yoruba- which is very important in Candomblé initiation rites in Bahia. In the first part of the recitals, the orator portrays the characteristics of different types of kamichis, particularly similar to the kamichi with corns known as iúna and as the unicorn of the Amazon, whose main feature is a corn at the top of the head. We find this bird in all regions of the Amazon in Brazil and in the north-eastern regions too. They are common in swamps, in ponds and other inundated territories; however, the kamichi with a corn can be distinguished by its deep, strong and melodious chants. The kamichi is apparently also able to emit ventriloquistic sounds or able to scare away animals by imitating the hissing of a snake. American-Indian myths assign mysterious powers to the kamichi. It is difficult to capture, it is considered as a sentinel in the forest and its corn, according to beliefs, has the ability to protect and heal snake bites.