The Lost Caverns of Ixalan

Cenote Scout | Creature | Merfolk Scout | When Cenote Scout enters the battlefield, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.) | Caroline Gariba

Ixalli's Lorekeeper | Creature | Human Druid | {T}: Add one mana of any color. Spend this mana only to cast a Dinosaur spell or activate an ability of a Dinosaur source. | Ernanda Souza

Jadelight Spelunker | Creature | Merfolk Scout | When Jadelight Spelunker enters the battlefield, it explores X times. (To have it explore, reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then put the card back or put it into your graveyard.) | Izzy

Seeker of Sunlight | Creature | Merfolk Scout | {2}{G}: Seeker of Sunlight explores. Activate only as a sorcery. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.) | Randy Vargas