First the exact description of the powers:
You can cast spells as if they were a higher level.Benefit: A heightened spell has a higher spell level than normal (up to a maximum of 9th level). Unlike other metamagic feats, Heighten Spell actually increases the effective level of the spell that it modifies. All effects dependent on spell level (such as saving throw DCs and ability to penetrate a lesser globe of invulnerability) are calculated according to the heightened level.
Level Increase: The heightened spell is as difficult to prepare and cast as a spell of its effective level.
Benefit: Pick one spell when you choose this trait. When you apply metamagic feats to this spell, treat its actual level as 1 lower for determining the spell’s final adjusted level.
Now let's say Gandalf the level 18 wizard knows the feat Heighten.
If Gandalf wants to memorize an heightened flesh to stone to level 9 (instead of level 6, the actual spell level of a flesh to stone), he has to memorize it in one of his level 9 slots.
So far so good...
Now let's say Gandalf has the trait Magical Lineage for the spell flesh to stone. If Gandalf wants to memorize an heightened flesh to stone to level 9, which level slot has he to use ?
I have the feeling, because of the magical lineage trait, that would be a level 8 slot but i d like confirmation.
Thanks for any answer !
That's my understanding as well; a spell heightened to level (N) would take a level (N-1) slot.
It would be a level 8 spell.