Each player mills two cards. Then you put a creature card from a graveyard onto the battlefield under your control.

Whenever you cast a creature spell that has an Adventure, Garenbrig Squire gets +1/+1 until end of turn. (It doesn't need to have gone on the adventure first.)

When Omenspeaker enters the battlefield, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)