When you cast the spell, you choose its targets before you pay for it.

The spell checks on resolution to see if any mana of the stated colors was spent to pay its cost. If so, it doesn't matter how much mana of that color was spent.

Moonhold is not a counterspell. It will have no effect on creature spells the targeted player cast before Moonhold resolved.

The spell cares about what mana was spent to pay its total cost, not just what mana was spent to pay the hybrid part of its cost.

The spell cares about what mana was spent to pay its total cost, not just what mana was spent to pay the hybrid part of its cost.

The spell checks on resolution to see if any mana of the stated colors was spent to pay its cost. If so, it doesn't matter how much mana of that color was spent.

If the spell is copied, the copy will never have had mana of the stated color paid for it, no matter what colors were spent on the original spell.

Moonhold doesn't stop effects that "put a card onto the battlefield."

If the spell is copied, the copy will never have had mana of the stated color paid for it, no matter what colors were spent on the original spell.