How Does Panharmonicon Work?

Panharmonicon affects an artifact or creature's own enters-the-battlefield triggered abilities as well as other triggered abilities that would trigger when an artifact or creature enters the battlefield. ... Panharmonicon's effect doesn't copy the triggered ability; it just causes it to trigger twice.

Does Panharmonicon work with cast triggers?

No. Panharmonicon doubles any trigger caused by a creature or artifact entering the battlefield. Prossh, Skyraider of Kher's triggered ability happens when you cast him, not when he enters.

Does Panharmonicon trigger landfall?

Since Panharmonicon only doubles ETB triggers from creatures and artifacts, these lands would allow me to double any landfall triggers when they come in. Here's the decklist, but there are seven landfall cards in the deck.