The game starts with no monarch. Once an effect makes one player the monarch, the game will have exactly one monarch from that point forward.
If the triggered ability that causes the monarch to draw a card goes on the stack, and a different player becomes the monarch before that ability resolves, the first player will still draw the card.
Entourage of Trest checks if youâ€™re the monarch only as blockers are declared. If it blocks two attacking creatures, another player becoming the monarch wonâ€™t change or undo that block.
Abilities that trigger whenever you â€œbecome the monarchâ€ trigger only if you arenâ€™t already the monarch. For example, if you are already the monarch as Custodi Lich enters the battlefield, its last ability wonâ€™t trigger.