Rush characters and Shifted Floodborns
If your budget is limited and your goal is collecting or investing, I recommend booster boxes first, ETBs for extras
Facilier: Agent Provocateur are another good Shift pairing, as getting the 7 cost Agent Provocateur into play early offers strong possibilities with 3 lore per quest and the Into the Shadows ability that allows banished characters to be returned to the hand
Red decks can get their hands on hard-hitting reprints like Scourge of the Throne and Combat Celebrant, which enable aggro strategies by giving the player extra combat steps
In Magic: The Gathering's latest set, The Brothers' War, we get a reprint of a commonly seen card Disfigure
Jitte was banned the last time they added it to a Secret Lair, and nothing ever came of that