At one point, before the Companion errata, this was the literal case
SET BOOSTER EXCLUSIVE CARDS Lost Caverns of Ixalan is the last set to have Set Booster exclusive cards (also available in extended and foils, in Collector Boosters)
Oftentimes, that last effort is all it takes to close out a game
The fact that these computers can do more often means that they do
(Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.) Legendary Creature - Advisor Dwarf Goblin Dark-Dwellers Menace (This creature can't be blocked except by two or more creatures.) When this creature enters, you may cast target instant or sorcery card with mana value 3 or less from your graveyard without paying its mana cost
Looter il-Kor Looter il-Kor used to be a Cube staple until the printing of Suspicious Stowaway and similarly pushed looters like Duelist of the Mind and Malcolm, Alluring Scoundrel