Pick one spell when you choose this trait. When you apply metamagic feats to this spell that add at least 1 level to the spell, treat its actual level as 1 lower for determining the spell’s final adjusted level.
When you use the chosen spell with a metamagic feat, it uses up a spell slot one level lower than it normally would.
You grew up on one of the wayang-populated islands of Minata, and your use of magic while hunting has been a boon to you. Select a spell of 3rd level or below. When you use this spell with a metamagic feat, it uses up a spell slot one level lower than it normally would.
If they stack, I could cast a Shocking Grasp with Intensified Spell (+1) Empower Spell (+2) with Magical Lineage (-1), Metamagic Master (-1) and Wayang Spellhunter (-1). So a 1st level Intensified Empowered Shocking Grasp. By the way, this spell should be recallable with a Pearl of Power (1st).
Do Magical Lineage, Metamagic Master and Wayang Spellhunter stack together?
Metamagic Master and Wayang Spellhunter are the same trait…
It’s unlikely that a GM will allow one creature to take both the Metamagic Master trait and the Wayang Spellhunter trait. Although both are regional traits and many GMs do ignore the rule that says that a creature can’t take more than one trait from each trait category (see here on Restrictions on Trait Selection), the traits are also the same trait: The d20PFSRD renamed and changed the description of the trait Metamagic Master to remove product identity from the trait Wayang Spellhunter. There’s no Metamagic Master trait in the Dragon Empires Primer as per its provenance on the d20PFSRD, only Wayang Spellhunter.
…But the benefits of Magical Lineage and Waywang Spellhunter can be combined
Except in rare case, bonuses of the same type or from the same source don’t stack, and, instead, only the highest bonus of the same type is applied. For example, the trait Elven Reflexes and the trait Reactionary each grant a +2 trait bonus (the bonus’s type) on initiative checks so a creature with both traits gains only a +2 trait bonus on initiative checks.
However, the benefits of the traits Magical Lineage and Waywang Spellhunter are not bonuses—and even different benefits—, so the two traits can work in conjunction.
This means that the benefit of the trait Magical Lineage can be combined with the benefit of the trait Wayang Spellhunter (i.e. Metamagic Master) to allow the creature to prepare in (or cast using) a 2nd-level slot an intensified empowered shocking grasp spell.