I was thinking about one of the Cleric's under-utlized Tricks, namely that of the Spell Domain Cleric using Anyspell to be able to cast Arcane Spells and Qualify for Mystic Theurge.
Lvl 1 Bard 1 Precocious Apprentice
Lvl 2 Cleric 1
Lvl 3 Cleric 2 Heighten Spell
Lvl 4 Mystic Theurge 1
Lvl 5 Mystic Theurge 2
Lvl 6 Mystic Theurge 3
Lvl 7 Mystic Theurge 4
Lvl 8 Mystic Theurge 5
Lvl 9 Mystic Theurge 6
Lvl 10 Mystic Theurge 7
Lvl 11 Sublime Chord 1
Lvl 12 Mystic Theurge 8
Lvl 13 Mystic Theurge 9
Lvl 14 Mystic Theurge 10
Lvl 15 Arcane Hierophant 1
Lvl 16 Arcane Hierophant 2
Lvl 17 Arcane Hierophant 3
Lvl 18 Arcane Hierophant 4
Lvl 19 Arcane Hierophant 5
Lvl 20 Arcane Hierophant 6
The above Build nabs Bard CL 8, Cleric CL 18, and Sublime Chord CL 11 (or higher depending on DM). It requires the DM to allow Bamboo Spirit Folk to qualify.
Lvl 1 Cleric 1
Lvl 2 Cleric 2
Lvl 3 Cleric 3
Lvl 4 Cleric 4
Lvl 5 Warlock 1
Lvl 6 Eldritch Disciple 1
Lvl 7 Eldritch Disciple 2
Lvl 8 Eldritch Disciple 3
Lvl 9 Eldritch Disciple 4
Lvl 10 Eldritch Disciple 5
Lvl 11 Eldritch Disciple 6
Lvl 12 Eldritch Disciple 7
Lvl 13 Eldritch Disciple 8
Lvl 14 Eldritch Disciple 9
Lvl 15 Eldritch Disciple 10
Lvl 16 Mystic Theurge 1
Lvl 17 Mystic Theurge 2
Lvl 18 Mystic Theurge 3
Lvl 19 Mystic Theurge 4
Lvl 20 Mystic Theurge 5
The above Build nabs Cleric CL 18, Warlock CL 16 which is enough for a Dark Invocation at level 20.
The problem with these builds is that they both lose 2 Caster Levels for Cleric. However, if one exchanged Bard for Wizard and did not take Sublime Chord
Lvl 1 Wizard 1 Precocious Apprentice
Lvl 2 Cleric 1
Lvl 3 Cleric 2 Heighten Spell
Lvl 4 Mystic Theurge 1
Lvl 5 Mystic Theurge 2
Lvl 6 Mystic Theurge 3
Lvl 7 Mystic Theurge 4
Lvl 8 Mystic Theurge 5
Lvl 9 Mystic Theurge 6
Lvl 10 Mystic Theurge 7
Lvl 11 Mystic Theurge 8
Lvl 12 Mystic Theurge 9
Lvl 13 Mystic Theurge 10
Lvl 14 Arcane Hierophant 1
Lvl 15 Arcane Hierophant 2
Lvl 16 Arcane Hierophant 3
Lvl 17 Arcane Hierophant 4
Lvl 18 Arcane Hierophant 5
Lvl 19 Arcane Hierophant 6
Lvl 20 Arcane Hierophant 7
This would net Cleric CL 19 and Wizard CL 18. I'm curious if this build is superior to the Sublime Chord one or not, and if this is as good as it gets.