In tournament play, this means your sideboard
1 Trainer hologram card, of which only seven exist
The reason full set spoilers came so late was because of R&Ds philosophy that the prerelease not just the weekend, but the actual event should be the first time you see the totality of the cards
As such, playing cheap ways to get token copies of Etali (regardless of whether they stick around) is the way to go
You have to sacrifice it when the final chapter resolves, removing a bit of your presence from the battlefield and leaving your board state a little less threatening
Three Warhammer Secret Lairs went on pre-order on October 17 - as with all Secret Lairs, that's the only time Wizards will sell them, so your only way to get their contents is from the secondary market