Whenever you cast a spell, each opponent reveals cards from the top of their library until they reveal a land card, then puts those cards into their graveyard
House, President and CEO Negan, the Cold-Blooded Neriv, Crackling Vanguard Neriv, Heart of the Storm Olivia, Opulent Outlaw Oros, the Avenger Piru, the Volatile Ponyback Brigade Queen Marchesa Reigning Victor Shanid, Sleepers' Scourge Snapdax, Apex of the Hunt Snapdax, Apex of the Hunt Sonic Shrieker Squall, Gunblade Duelist Syr Gwyn, Hero of Ashvale Tariel, Reckoner of Souls Terra, Herald of Hope Thanos, the Mad Titan Vihaan, Goldwaker Zurgo Helmsmasher Zurgo Stormrender Zurgo, Thunder's Decree
So the answer at present is that we simply dont know but we wouldnt be surprised if the popular Trainer Gallery cards do make another appearance at some stage.
Tough Cookie is even more flexible with the addition of its middle ability, which is useful for not just its own Food token, but any of the cheap artifacts found in Wilds of Eldraine , such as Prophetic Prism, Soul-Guide Lantern, Candy Trail, and Collector's Vault
