Explorers of the Deep

Explorers of the Deep is a 100-card Commander precon from The Lost Caverns of Ixalan Commander, released November 17, 2023. It is led by Hakbal of the Surging Soul, a Simic commander.

Hakbal of the Surging Soul

At the beginning of combat on your turn, each Merfolk creature you control 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 the exploring creature, then put the card back or put it into your graveyard.)
Whenever Hakbal attacks, you may put a land card from your hand onto the battlefield. If you don't, draw a card.

The list runs 36 lands and 37 creatures, and its nonland cards average 3.03 mana. At today's TCGplayer prices the whole deck's cards come to about $100.41, and the most valuable is Herald of Secret Streams at $9.64.