Because both of these effects are applied on the same layer 6 and they do not depend on each other, so they are applied according to the timestamps
Some players want explosive mana combos, while others may prefer grinding value or overwhelming opponents with tokens
Give yourself at least a week's lead time for group orders so you have room to finalize all the photos and designs before you need the cards in hand
When you finish your Main phase, play goes to the End phase, which acts as a clean up step for end of turn effects and the like
A few clarifications for those readers who are unsure how Omen Machine (and such similar effects instructing players to cast a card) works: When an effect instructs a player to cast a card ("if able"), and there is no word "may", that means that the player has no choice, and is forced to cast the card, if it can be legally cast
You dont have to pay the ward cost