Explorers of the Deep Upgrade Guide

Quick verdict

Explorers of the Deep is a Merfolk deck that gets a free card or a bigger creature from every Merfolk on its board each turn, which makes it one of the easier precons to keep fueled. Hakbal of the Surging Soul makes each Merfolk explore at the start of your combat, so a board of four Merfolk sees four extra cards a turn. The weak spots are a top end that costs too much for what it does, very little protection against a board wipe, and almost no way to stop an opponent's spell.

TurnZero HQ rates Explorers of the Deep a 2 out of 5 on difficulty and a 3 out of 5 on power, as it comes in the box. That is our editorial read, not an official Wizards rating. The full hundred cards are on the Explorers of the Deep decklist page, and every other precon we cover is on the precon directory.

How the precon plays

Hakbal of the Surging Soul does two jobs. At the beginning of combat on your turn, each Merfolk you control explores: it reveals the top card of your library, you keep it if it's a land, and otherwise the Merfolk gets a +1/+1 counter and you choose whether to leave the card on top or put it in the graveyard. When Hakbal attacks you either put a land from your hand onto the battlefield or draw a card. Every turn you have Merfolk out, you either hit land drops or grow the team.

The rest of the deck is built to turn those counters into damage. Herald of Secret Streams makes every creature with a +1/+1 counter unblockable, Hardened Scales and Branching Evolution add more counters to every explore, and lords like Merfolk Sovereign , Master of the Pearl Trident and Merfolk Mistbinder pump the whole tribe. Topography Tracker makes each explore happen twice, which doubles Hakbal's output on its own.

The deck's card advantage comes from the same place. Kindred Discovery draws a card whenever a Merfolk enters or attacks, Seafloor Oracle draws on combat damage, and Tatyova, Benthic Druid draws off every land the explores put into your hand.

What works out of the box

Hakbal of the Surging Soul ↗

Explores with every Merfolk at the start of combat, so the deck's card quality and its counters both scale with the size of the board.

Herald of Secret Streams ↗

Creatures with +1/+1 counters can't be blocked. In a deck that puts a counter on most of its creatures every turn, this is usually the card that ends the game.

Topography Tracker ↗

Each explore happens twice. With Hakbal out, that is two cards' worth of selection and up to two counters per Merfolk each turn.

Kindred Discovery ↗

Draws a card whenever a Merfolk enters or attacks. Naming Merfolk here gives the deck a draw engine that refills it every turn.

Inspiring Call ↗

Draws a card for every creature with a +1/+1 counter and makes them indestructible. It answers a destroy-based board wipe and refills your hand at the same time.

Simic Ascendancy ↗

Every counter Hakbal adds also goes on this enchantment, and twenty of them win the game. Many games end with this card getting there first.

What needs improvement

The top of the curve is soft. Xolatoyac, the Smiling Flood is six mana for a creature that is not a Merfolk and does nothing with Hakbal, and Mist Dancer is a five-mana lord when Merfolk Sovereign does a similar job for three. A Merfolk deck wants to put creatures down quickly, before the first board wipe, and these slow it down.

There is very little interaction. Apart from Rapid Hybridization , Curse of the Swine and a couple of bounce spells, the deck has no way to stop an opponent's spell or answer a combo. It also has very little that protects the board, so one board wipe can undo four turns of counters. See how much removal a Commander deck needs for a number to build toward.

Upgrade ideas

Each upgrade below starts from something the deck does poorly and says what a replacement card has to do. The cards named are examples, not the only answer: if you own something else that does the same job, or a newer printing does it better, it goes in the same slot. Make one change at a time and play a few games between them, so you can tell which change helped. The general method is in how to upgrade a Commander precon →

1. Protect the board from a wipe

This deck's whole plan is a wide board of Merfolk with counters on them, which is exactly what a board wipe punishes. Right now the only real insurance is Inspiring Call .

What to look for Instant-speed cards that give your whole team indestructible or hexproof, ideally for two or three mana so you can hold them up while still developing.

Cut, for example

✕

Aetherize A fog that returns attackers to hand. It buys a turn against one attack, but it is four mana you have to keep open, and it does nothing about a wrath.

✕

Mist Dancer A five-mana lord that gives other Merfolk flying. Herald of Secret Streams already gets the team through, and three-mana lords do the pumping.

Add, for example

Heroic Intervention ↗

Two mana at instant speed: everything you control gains hexproof and indestructible for the turn. It stops most board wipes and any single removal spell.

Simic Charm ↗

Gives your permanents hexproof against targeted removal, or bounces a blocker, or pumps an attacker. Flexible and cheap.

Tamiyo's Safekeeping ↗

One mana to protect Hakbal or a key creature like Herald of Secret Streams from a targeted removal spell.

2. Lower the curve with cheaper Merfolk

Hakbal rewards having many Merfolk on the battlefield on turn four or five. Every six-drop that isn't a Merfolk is a turn the deck spends not doing what it wants to do.

What to look for Merfolk costing two or three mana that either pump the tribe or replace themselves with a card. Every Merfolk you add is one more explore each turn.

Cut, for example

✕

Xolatoyac, the Smiling Flood Six mana for a creature that isn't a Merfolk and doesn't explore. Its untap ability is cute with counters but rarely matters.

✕

Surgespanner Four mana for a 2/2 whose bounce costs another two mana every time. Too slow for what it does.

✕

Kiora's Follower A two-mana Merfolk whose untap ability has almost no good targets in this deck.

Add, for example

Lord of Atlantis ↗

Two mana: other Merfolk get +1/+1 and islandwalk. One of the cheapest lords there is, and it brings Hakbal's team online early.

Silvergill Adept ↗

Two mana and it draws a card when it enters, as long as you reveal another Merfolk from your hand. It adds a body and replaces itself.

Merfolk Trickster ↗

Two mana with flash. It taps a blocker or switches off a creature's abilities for a turn, and it is another Merfolk to explore.

3. Add interaction that stops a spell

The deck can remove creatures but can't stop an opponent's board wipe, combo piece, or game-winning spell. Two or three counterspells change that, and blue has plenty of cheap ones.

What to look for Counterspells or ability counters costing three mana or less. A Merfolk with flash that counters something counts twice.

Cut, for example

✕

Commit // Memory Commit is a fine four-mana answer, but Memory refills every player's hand, which helps opponents as much as you.

✕

Sage of Fables Its bonus only applies to Wizards, and its card draw costs you a +1/+1 counter, which works against Hakbal's plan.

Add, for example

Counterspell ↗

Two mana, counters anything. The baseline every other counterspell is measured against.

Tishana's Tidebinder ↗

A three-mana Merfolk with flash that counters a triggered or activated ability, and strips a creature's abilities while it stays on the battlefield.

Swan Song ↗

One mana to counter an instant, sorcery, or enchantment. Most board wipes are one of those.

4. Get more from every land Hakbal finds

Hakbal keeps putting lands into your hand, and it can drop one onto the battlefield when it attacks. Cards that reward land drops turn that stream of lands into mana or cards.

What to look for Creatures or enchantments that let you play extra lands, or that give you something whenever a land enters.

Cut, for example

✕

Temple of the False God Taps for nothing until you control five lands, which makes it a blank on the turns you need mana most.

✕

Stonybrook Banneret A 1/1 that makes Merfolk cost one less. Better ramp does more for this deck.

Add, for example

Oracle of Mul Daya ↗

Lets you play an extra land each turn and play lands from the top of your library, so explores that reveal a land don't stall.

Lotus Cobra ↗

Adds a mana of any color whenever a land enters, including the one Hakbal puts down when it attacks.

Exploration ↗

One mana for an extra land drop every turn. Cheap, and it keeps paying off as long as Hakbal keeps handing you lands.

5. Draw cards from creatures entering

The deck plays a lot of creatures, many of them different. A draw engine that triggers on creatures entering keeps the hand full after the first wave is down.

What to look for Enchantments or creatures that draw when a creature enters, which every Merfolk you cast then triggers.

Cut, for example

✕

Ravenform A sorcery-speed exile spell that gives the creature's owner a 1/1 flier. Rapid Hybridization and Curse of the Swine already cover creature removal.

Add, for example

Guardian Project ↗

Draws a card whenever a nontoken creature with a new name enters. Almost every Merfolk in this deck is a one-of.

Rishkar's Expertise ↗

Draws cards equal to your biggest creature's power, then casts a free spell. With counters stacking up, that is usually five cards or more.

Win conditions

The upgraded deck still wins the way the precon wanted to. Put down cheap Merfolk, let Hakbal of the Surging Soul put counters on them each combat, and attack through Herald of Secret Streams or islandwalk once the lords are out. Simic Ascendancy is the backup plan in a long game, since every counter Hakbal places also goes on it. The changes above mainly make sure the board survives long enough to do that.

Who should buy this precon

A good pick for someone who likes tribal decks and wants a commander that does something every turn without much to track. The explore triggers ask for one small decision each (keep the card on top or bin it), which is a good way to learn card selection. It is less suited to a player who wants a deck that interacts heavily with opponents, since that takes the upgrades above.

Checked against the printed decklist on October 10, 2026.