New to the Missa Cantata?

Me too!  And I have been quite confused until I understood what the Kyriale is(yes this probably sounds crazy to some, but I searched for a long time trying to find out where the list of all the possible selections were located).  

The Kyriale is a collection of Gregorian chant settings for the Ordinary of the Mass. It contains eighteen Masses (each consisting of the Kyrie, Gloria, Sanctus, and Agnus Dei), six Credos, and several ad libitum chants. This collection is included in liturgical books such as the Graduale Romanum and Liber Usualis, and it is also published as a separate book by the monks of Solesmes Abbey.

Some of the more notable inclusions are Mass VIII which is the Missa de Angelis and Mass XI which is the Missa Orbis Factor.

Here is a list of the sets:

 Missa I - Lux et origo (for the Easter season)
 Missa II - Kyrie fons bonitatis
 Missa III - Kyrie Deus sempiterne
 Missa IV - Cunctipotens Genitor Deus (for feasts of apostles)
 Missa V - Kyrie magnae Deus potentiae
 Missa VI - Kyrie Rex Genitor
 Missa VII - Kyrie Rex splendens
 Missa VIII - de Angelis
 Missa IX - Cum jubilo (for Marian solemnities and feasts)
 Missa X - Alme Pater (for Marian feasts and memorials)
 Missa XI - Orbis factor (for Sundays)
 Missa XII - Pater cuncta
 Missa XIII - Stelliferi Conditor orbis
 Missa XIV - Jesu Redemptor
 Missa XV - Dominator Deus
 Missa XVI (for weekdays during Ordinary Time)
 Missa XVII (for Sundays in Advent and Lent)
 Missa XVIII - Deus Genitor alme (for weekdays in Advent and Lent)

No mixing and matching here like Kyrie from Missa VIII and Gloria from Missa XI.  The one exception is the Credo which has 6 selections in the Kyriale, Credo I - VI.  I think the most standard is "Credo I" but I could be wrong.  How cool would it be to sing the Credo in the Ordinary Form; singing instead of saying what I believe is so much more powerful.   Even outside of Church, hearing a stadium full of people singing the national anthem is quite moving.  We don't just believe it, we REALLY believe it!  Coming from a hymn based background it's cool to see the Universal Church has put together a guide to help us elevate our minds and souls at the heavenly banquet.  This is how many of my favorite saints would have sung the Mass! 

Thanks to Wikipedia for this info.  Now next is to figure out how to sing them!  :-\  :-o