How Mythic Spellbook Merging works, and why Lich & Angel are so STRONG

[cRPG Bro]

https://www.youtube.com/watch?v=PgzYvRCcFpM
If you've ever heard Merged Lich & Angel are some of if not the strongest Mythics in the game, here is the simple reason: Spellbook Merging. There are three basic points you need to understand about merging:

1. First, what can merge: currently, only the FULL Divine or Arcane spellcasters can merge.
Full Spellcasting means having access from level 1 to level 9 spells.
Full Divines get to merge with Angel, so Cleric, Oracle, Shaman and Druid.
Full Arcanes get to merge with Lich, so Wizard, Sorcerer, Arcanist & Witch.

2. Second, when to merge: you get to merge at Mythic Rank 3, by choosing the second option called Mythic Spellbook (your full caster class name).

3. Third, and most importantly, what merging actually does:
3.1 It adds ALL the unique Lich & Angel Mythic Spells to your main Spellbook. This results in way more casts because you have a lot of more slots, which can also be increase through the Abundant Casting line of Mythic Abilities, which actually do NOT work for Mythic Spellbooks, only normal Spellbooks (which is what your Merged Spellbook is, except with the addition of Mythic Spells to it).
It's also especially useful for spontaneous casters like Sorcerer & Oracle because you automatically learn ALL of your unique Mythic spells at once as you reach a new spell level.
3.2 Most importantly, It supercharges your spellcasting progression by adding EVERY Mythic Level you have as +1 to both Caster Level and also for spells known/spell learning purposes.
This means a Level 10 Cleric Angel with 3 Mythic Levels has the equivalent of 13 CL, and can actually cast up to level 7 spells, instead of just level 5, which would be the norm for a level 10 full caster.
Also their variable effects that are reliant on Caster Level will also treat it as 13, such as spell damage & duration.
The power gained from this is simply immense. For example, you can have 9th spells just at Chapter 3, by having 13 levels in let's say Wizard, and then 4 Mythic Rank.
And eventually 30 Caster Level, as opposed to just 20 CL, which means way more damage and uncapped effects in the powerful spells like Storm of Justice and Negative Eruption or Feast of Blood. Some defensive buffs too like Magical Vestment.

[brownacs]

Throw in that Lich cloak too. + 9 to CHA, STR and DEX... on top of the + from Nocticula and the belts, the hats and the buffs. My Lich has 62 STR and I think I could've gotten it higher. Love your channel by the way, keep up the good work!

[Player#2201]

There are still some (seemingly unintended) gaps in functionality for classes. Currently playing merged Cleric/Angel with some issues; 10th level spell domain slot cannot be filled even with heighten metamagic feat on other domain spells, 9th level spells cannot be readied with with metamagic despite having the Favored MM mythic ability reducing level adjustment to zero, and some Angel specific spells can't apply metamagic feats at all despite meeting the prerequisites for it (ex. cleansing flame + bolster).

As is - the options are still satisfyingly OP, but so far the classes with least amount of bugs that support this topic seem to be spontaneous casters.

[revan1229]

I really hope some balance is brought to the paths in this regard. Some of the other paths can eventually catch up to a degree in the late game (like Azata casters and crit Tricksters), but the immediate jump in power from this feature alone is kind of ridiculous.

Originally posted by Player#2201:

As is - the options are still satisfyingly OP, but so far the classes with least amount of bugs that support this topic seem to be spontaneous casters.

This game seems to favor spontaneous casters all around.