An ability that triggers when a permanent becomes the target of a spell resolves before the spell that caused it to trigger. It resolves even if that spell is countered.

If a spell targets Myriad Construct more than once, its last ability triggers only once.

If you don't sacrifice Myriad Construct as its last ability resolves (perhaps because its ability triggered more than once and you've already sacrificed it), you still create Construct tokens. The number of tokens you create is determined by Myriad Construct's power as it last existed on the battlefield.

The kicker ability doesn't let you pay a kicker cost more than once.

If you put a permanent with a kicker ability onto the battlefield without casting it, you can't kick it.

If a card or token enters as a copy of a permanent, the new permanent isn't kicked, even if the original was.

If a spell's kicker cost was paid, the spell is "kicked."

To determine a spell's total cost, start with the mana cost (or an alternative cost if another card's effect allows you to pay one instead), add any cost increases (such as kicker), then apply any cost reductions. The spell's mana value remains unchanged, no matter what the total cost to cast it was.

If you copy a kicked spell on the stack, the copy is also kicked. If the copied spell is a permanent spell, the token the copy of that spell becomes when it enters is also kicked.