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The Forgetful Fish Format
Author: Ben Guilfoyle
This piece is a love letter to Forgetful Fish – a shared-deck, mono-blue mini-format born in 1997 where two players draw from the same 80-card stack and try to win with exactly one threat: Dandân. It explains the rules, the card philosophy (islands matter + top-deck warfare), the newly revealed Secret Lair version, and how to tune the experience to your table.
This article focuses on:
- What It Is & Why It’s Fun. Two players, 20 life each, one communal deck. Ten Dandân are the only win condition; islands enable and endanger them. The format plays like a tight board game or micro-cube where every attack and draw step really matters.
- Deck Anatomy & Play Patterns. The classic list runs 80 cards (18 Islands, 10 Dandân, 6 Memory Lapse, 4 Accumulated Knowledge, most others as two-ofs). Games hinge on stack battles (tons of instants), top-deck manipulation, and the “do I play an Island?” sub-game that gates both offense and interaction.
- Secret Lair Update. The SL build swaps in extras like Magical Hack, Control Magic, Mental Note, Capture of Hangzhou, and utility lands (Haunted Engram, The Surgical Bay), while cutting pieces like Ray of Command and Mystical Tutor. Vision Charm moves to a bonus slot. Author’s warning: replacing Diminishing Returns with Day’s Undoing likely prolongs games.
- Variants & Community. Linked lists cover Floyd’s original, the SL approximation, tempo-leaning “Good Dandân,” and even red “Hollow One” riffs—plus nods to Battle Box for adjacent, self-contained experiences.
- Tuning Tips. Choose cards that promote the gameplay you want: consider Take Inventory over Accumulated Knowledge, add shuffle effects (Lórien Revealed), curb the “no Island” stalemate with cantrip land-changers, and prioritize interaction that keeps turns brisk and decisions sharp.
The Setup
Forgetful Fish is blue Magic at its purest. Carbon compressed into a diamond. A format with one deck shared between two players. With an upcoming Secret Lair, now is a good time to discuss this wonderful way to play Magic.
Forgetful Fish is the brainchild of Nick Floyd in 1997. The idea came about when:
“travel(ing) to see cousins and left my cards at home. I did however buy some Homelands and Chronicles packs on the road as well as a starter deck of 4th Edition. Not having enough cards or lands to build two decks, I shuffled all the cards I had together, and I taught my cousin how to play with just one deck.”
Within that jumble of cards was Dandân, Memory Lapse and the skeleton of a new way to play.
What is Forgetful Fish?
Play Forgetful Fish like any other game of Magic. Each player has 20 life. You lose if you reach zero life. The difference, the players draw from a shared deck. This makes Forgetful Fish a closer to Cube, or even a board game.
The deck’s one and only threat is ten copies of Dandân. For two mana you get a 4/1. It dies if you do not control an Island, and cannot attack unless the defending player controls an Island. Four power means five attacks from the fish is lethal. With no other way to deal direct damage, each attack matters.
The Island-matters theme continues throughout the deck. There are many effects that interact with lands or Dandân‘s ability. Mind Bend and Crystal Spray are useless in most decks. Here they are powerful instant speed kill spells.
The second major piece of the puzzle if top-deck manipulation.
Memory Lapse has a whopping six copies in the deck. Fighting for control of the top card makes this format so unique. With all the top deck manipulation, there are plenty of cantrips to take advantage. Predict becomes much more consistent. Mystical Tutor is a risky play when your opponent plans to draw it ahead of you. Brainstorm involves planning out you and the opponent’s next few turns.
For all these strange card selections, Forgetful Fish is a shared mono blue experience.
The Deck in Detail
Forgetful Fish is an 80 card deck. Within there are 18 Islands, 10 Dandân, 6 Memory Lapse, 4 Accumulated Knowledge. Everything else is two copies.
Floyd’s original 1997 version was a 60 card list with a similar construction. Two of everything with bonus copies of Dandân, Memory Lapse and Accumulated Knowledge. You can find both deck lists below.
Lands
Forgetful Fish leverages its lands to further push its gameplay. Halimar Depths, Mystic Sanctuary, and Temple of Epiphany give you top deck knowledge. Lonely Sandbar and Remote Isle let you draw a card without exposing yourself to counterspells.
Svyelunite Temple and Izzet Boilerworks give you extra mana from one land at a cost.
18 Islands round things out. That’s 19 lands with type “Island” out of 32. This leads to some critical decision-making around when to play an Island. Your opponent’s fish cannot attack you if you don’t play an Island. But, if you never play an Island, you can never cast a fish. Depending on your play style, this can lead to an amazing, or frustrating control sub-game. We will discuss this again in more detail throughout the article. Try to consider how you would hinder or help this strategy.
On the Stack
Forgetful Fish loves battling on the stack. 34 instants means every open mana matters. Besides Memory Lapse we have Unsubstantiate to unsummon the fish. Insidious Will is a two-for-one if you redirect an opponent’s spell.
Blue is not renowned for combat tricks. Dance of the Skywise was one of my favorite spells in Tarkir Limited. This is a powerful way to get those last crucial points of damage. Ray of Command plays a similar role. If an opponent has multiple fish in play, you can steal one of them to block the other.
Sorcery Speed
Mystic Retrieval is a cute novelty for this format. It returns a spell from grave to hand. The red flashback cost is only possible thanks to Izzet Boilerworks works and Temple of Epiphany. Red plays no further role besides Mystical Retrieval.
Diminishing Returns if a wheel effect that exiles the top ten cards of your deck. That second half is surprisingly relevant. It prevents the game going too long. Diminishing Returns thins the deck by 10 cards each. Diminishing Returns does not exile itself. This makes it possible in a long game to thin the deck down to nothing.
With less interaction, Fish, and cards in deck you can begin to secure a win. This could even tie into the “don’t play any Islands” game plan if you want to try to mill your opponent. Diminishing Returns is the glue that holds the deck together.
Secret Lair Chaos Drop: Forgetful Fish
The Secret Lair (SL) edition of Forgetful Fish features a full 80 card deck plus two copies of a bonus card. It is not the exact Floyd list we have discussing up to now, but it is pretty familiar. All the cards feature either new borderless artwork, or a retro frame.
The Secret Lair deck list is not officially available yet, but it has been shown off at events such as MagicCon. Here’s a copy of the list from Moxfield user Trips. It does not feature all the new artwork yet, but the card contents are correct.
What’s the Difference?
Here is a quick comparison:
New Additions to Secret Lair
2 Island
Exclusions from Secret Lair
Sideboard
2 Vision Charm (Bonus card)
Let’s take some time to look at these changes and how they impact gameplay.
Lands
The SLD list adds two copies each of Island, Haunted Fengraf, and The Surgical Bay bringing us up to 34 lands. I love Fengraf’s inclusion. Before there was not a consistent way to return Dandân from the grave. The Surgical Bay forces the opponent to slow down and consider the top card. It sits in play as a constant reminder that you can, and will, steal the top card if they let you.
These lands replace Temple of Epiphany, Izzet Boilerworks and Mystic Retrieval. Without the red flashback spell, there is no need for these dual lands. Perhaps WOTC did not like the visual clash of red lands in a mostly mono-blue experience. A side effect of this is there is now no way to bounce your own lands. This goes some way to address the “I refuse to play an Island strategy”. Opponents can no longer use Boilerworks to pick up their Islands in an attempt to slow down the game.
Counter Your Counter
Memory Lapse replaces Insidious Will. This is a swap I’ve seen many lists make in the past. Insidious Will sometimes ends up stranded in your hand due to its higher mana value. Memory Lapse plays more into the top deck manipulation angle.
Dandân Killers
Vision Charm is gone from the main deck, but is still available with new art as a bonus card. This is another great move. The one mana board wipe is too powerful. I do not enjoy getting blown out by one card for one mana. It is also an icon of Forgetful Fish. I am glad to see it included for those who enjoy it.
A less powerful change is Mind Bend for Magical Hack. At first glance, they are very similar effects. Both will kill a Dandân. But, Magical Hack also affects spells on the stack.
You can change the working of Dandân while it’s on the stack. It will then die the moment it enters the battlefield. This could be useful during a counterspell war. It may also be useful if you make changes to your deck list. You could make Engulf the Shore care about Mountains instead of Islands. This is a minor upgrade, but a welcome one.
Fighting for Control
Control Magic replaces Ray of Command. This feels more in line with blue’s color identity. Ray of Command is a really jarring effect on a blue card. For new Forgetful Fish players, they would never expect this effect. Control Magic feels more at home here.
While not a theft effect, Supplant Form plays a similar role. It removes a fish and gives you one of your own. This plays very like Ray of Command but at a higher mana value. This card generates tokens. Removing this card means Forgetful Fish is an all-in-one ready to go game. No tokens, no counters, just the cards in the deck.
Top of the Curve
Capture of Jingzhou gives an extra turn for five mana. This rewards casting your fish early rather than holding back. You can swing, cast Capture, and win. Supplant Form and Ray of Command reward a slower game and punish players for casting the fish.
Capture of Jingzhou is also more powerful thanks to Vision Charm being removed. The aggressive game plan has a new pay-off and their main predator is gone.
There are other extra turn spells that could take this slot. Temporal Manipulation and Time Warp are identical replacements. Temporal Trespass and Temporal Mastery both fit the Forgetful Fish gameplay style, but are likely too powerful. Savor the Moment could be interesting, but I have yet to test it.
Cheap Draw
We have three new cheap draw spells in Mental Note, Telling Time, and Chart a Course.
Mental Note is an awesome inclusion. Milling cards is great in this format. It’s also a great reprint for Pauper players. This card has only seen print in Judgment and The List. This makes it a €7 – €10 card!
If you’re on a budget building this deck from scratch, consider Thought Scour instead. Pauper players usually run both cards so they don’t get a choice.
Telling Time is one of my favorite cantrips. You can cause a lot of trouble for your opponent with this. I have been running it in my personal list for years and love it.
Chart a Course is another card that encourages attacking with your fish. It may be worth it in a messy board to offer a trade to get good value out of this. I like the inclusion, as anything that pushes players to commit to the board is worth it!
Miscellaneous Removals
Dance of the Skywise is out. It is a weird spell and I can understand it leaving. Like Ray of Command it can feel a bit out of place in the format.
Mystical Tutor was also removed. It is much weaker in this format. Often your opponent will steal the card from under you. Neat in concept, bad in practice.
Diminishing Returns
Every change so far I understand. I do not agree with all of them, but I can see the intent behind it. Removing Diminishing Returns and replacing it with Day’s Undoing makes no sense to me. Day’s Undoing shuffles both player’s hand and grave into the deck, you then each draw seven cards. The turn then ends. This is the closest you can get to Timetwister without directly reprinting it.
Most the changes we’ve seen in the SL list push toward more active games. They want games to end, not drag out. But Days Undoing is the opposite. It drags things out. Go ahead and re-read the Diminishing Returns section from before. It is such a key piece of the puzzle in making sure even long control games come to an end.
If you buy this deck, replace Day’s Undoing as soon as possible. You can even buy a Sixth Edition or Alliances versions to keep the retro border theme! Or if you love long games just play Timetwister like the original 1990s list.
Teach a Man to Fish
The joy of Forgetful Fish is customization. While Floyd‘s version is excellent, there is always work to be done. Below is my personal list. It is a mixture of cards I enjoy, and a some substitutes based on what I owned.
Forgetful Fish now has its own “Format” section on Moxfield. Within you can find variants of our fishy friend, and even more creative variants. Braden‘s “Tempo/Good Dandân” is one of the more popular variants. The deck list is familiar, but makes changes to foster a tempo play style. Notable additions include Chart a Course and Gone Missing. He also omits Vision Charm. A one-sided board wipe for one mana is too much of a blowout.
As you move through the “Forgetful Fish” format, we stray from the mono blue roots. “Hollow Inquiries” by Viral Drake is a mono red variant that focuses on Hollow One. The deck uses 10 Hollow One, and two copies of everything else like the original. But here, the gameplay focuses on discarding cards to cheat Hollow One into play.
Forgetful Fish shares some DNA with Battle Box, another self-contained Magic variant. For now, I won’t go into Battle Box or Forgetful Fish variants further. But, Lucky Paper Radio has a great article on the topic if you’re curious.
Classic Forgetful Fish Improvements
Whether you buy the SL, or Floyd‘s, list as your starting point, consider the type of gameplay you want to foster.
Here are some cards to help improve your games!
Accumulated Knowledge vs Take Inventory
These two cards are almost identical. As the game goes longer, they grow in power.
Accumulated Knowledge is an instant, Take Inventory is a sorcery.
I prefer Take Inventory. I noticed players would hold their Accumulated Knowledge. Always waiting for the right moment to swoop in for value. Players could hold up counter magic and a draw spell all at once. Take Inventory forces players to make a choice between interaction and card advantage. I have enjoyed the more active gameplay it brought.
This is a key point for Forgetful Fish, Cube, and even casual Commander. Pick the cards that are right for your environment. Don’t always pick the most powerful option.
Surveil Lands
This is an easy upgrade if you’re keeping the Mystic Retrieval package. Play Thundering Falls over Temple of Epiphany. You can now leverage the graveyard more effectively at very little cost.
Shuffle Effects
Most the top deck manipulation occurs with cantrips, or effects that control the top. Sometimes it’s good to just shuffle the deck. Lórien Revealed is a great option. It can shuffle the deck, find lands, or be a draw spell in longer games.
Forced Islands
If the “refuse to play an Island” strategy is something you want to avoid, consider these:
Jinx Spreading Seas, Shimmering Mirage, and Lingering Mirage offer variations on a cantrip that turn a land into an Island. Some of these function more as one-off combat tricks, allowing the fish to swing in. Others are permanent effects that your opponent needs to deal with.
For a similar effect, you could try to remove Dandân‘s negative effect with Dress Down, or the already included Dance of the Skywise.
Conclusion
Forgetful Fish is a wonderful way to play Magic.
The gameplay is deep with a strong community behind it. Whether you go for the Secret Lair, or buy the singles to make your own deck, let us know how it turns out! Check out Three for One Trading for great deals on Forgetful Fish staples.
About the Author
Ben Guilfoyle started playing Magic in 2015. They love to research the design of Magic. Why was this card banned? Could this silver border card actually see play? Cards that push the limits of design is what excites them. You can usually find them playing cube. This ties into their second passion: numbers. With a background in physics and statistics, they love to get in the weeds when building decks. Crunching numbers is their specialty.
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