This is because of the update frequency between what's shown in the app and what you can see in the store's website
Card advantage is a strategic concept (rather than a specific game term) and a lot broader, and basically means having more cardboard than my opponents. For starters, any card that puts more cards in your hand is card advantage, even if it doesn't say draw. But card advantage also looks at what happens in other zones
However, if players already have a Mickey Mouse card in play, Artful Rogue can be summoned and played on top of that card for only 5 ink
Before the stream started, a message stated that the video was pre-recorded before the events of this week, and followed with this message: From there, they jumped into the new card reveals
The Cabaretti Cacophony Commander deck is for players who like to "play loads of low-cost creatures"