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

Glowcap Lantern | Artifact | Equipment | Equipped creature has "You may look at the top card of your library any time" and "Whenever this creature attacks, 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 that creature, then put the card back or put it into your graveyard.) Equip {2} | Irina Nordsol

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

Malamet Battle Glyph | Sorcery | | Choose target creature you control and target creature you don't control. If the creature you control entered the battlefield this turn, put a +1/+1 counter on it. Then those creatures fight each other. | Andrew Mar

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

Twists and Turns | Enchantment | | If a creature you control would explore, instead you scry 1, then that creature explores. When Twists and Turns enters the battlefield, target creature you control explores. When a land enters the battlefield under your control, if you control seven or more lands, transform Twists and Turns. | Deruchenko Alexander