#davidh

Majestic Myriarch has actually received post-printing, pre-release errata for the ability in question. Its new text is this:

At the beginning of each combat, Majestic Myriarch gains flying until end of turn if you control a creature with flying. The same is true for first strike, double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, reach, trample, and vigilance.

This is now the same style of templating as Odric’s ability, with no intervening if clause. It’s only a single trigger and it only checks for the relevant abilities when the trigger resolves.

This change was made for the same reason that you ask the question, as it would have been a very confusing ability indeed if it had stuck to its printed wording.

When Clone goes to enter the battlefield under your control, both Clone’s own replacement effect and Essence of the Wild’s replacement effect want to modify how it’s going to enter the battlefield. As Clone’s controller, you choose which of the effects to apply to the Clone first.

If you apply Clone’s replacement effect first, then you can choose a creature for it to enter the battlefield as a copy of. After that choice is made, the game once again checks to see if any replacement effects want to modify how Clone would enter the battlefield. Essence of the Wild’s replacement effect is still applicable, so it will be applied to Clone and Clone will ETB as a copy of Essence of the Wild instead of whatever you chose for its own ability.

If you apply Essence of the Wild’s replacement effect first, then Clone will become a copy of Essence of the Wild. The game then checks to see if any replacement effects want to further modify how Clone will enter the battlefield, but there are none. Clone’s own replacement effect no longer exists because Clone is now a copy of Essence of the Wild and not a Clone anymore. Since there are no further effects to apply, Clone enters the battlefield as a copy of Essence of the Wild.