This is a deck I made for someone on Fiverr. If you want a deck built, you can find me on Fiverr.com as Genoslugcs or by searching "MTG deck building."

The Deck

So, as mentioned, we have Merfolk tribal here. This works well with this commander duo because, besides a card advantage powerhouse, Thrasios, Triton Hero is also a Merfolk. Ravos, Soultender isn't a Merfolk, but he is a lord (giving +1/+1) to all our creatures and allowing us to recur and recast the creatures we may lose.

Merfolk And Tribal Payoffs

37 of the 40 creatures we're playing are Merfolk. So, I won't go over every single one. Instead, I want to go over some of the things we'll achieve by playing them. In other words, the payoffs. First up, we have lords.

In general, Merfolk are good because they're disruptive and problematic to block when they work together and aren't known for their high power and toughness. However, as a tribe, they have the best lords in the game. Cards like the ones you see above help turn a wide board of even small creatures into formidable threats. Aside from the ones pictured, we also have plenty of ways to bolster our creatures:

• Vodalian Wave-Knight
• Svyelun of Sea and Sky
• Mist Dancer
• Merrow Reejerey
• Mirror Entity
• Deeproot Elite
• Merfolk Mistbinder
• Vanquisher's Banner
• Mirari's Wake
• Door of Destinies

Disruption

As mentioned, Merfolk are great because they are disruptive to opposing strategies. This means you can interact with opposing threats while simultaneously adding to your own threats. There is a lot of synergy between these spells and Singer of Swift Rivers, which allows you to flash in creatures.

For example, you can use the ability with Merrow Reejerey (which can tap and untap things) to flash in Merfolk and tap opposing attackers or blockers. You can flash a Lord of Atlantis in during combat for extra damage. You can flash in Mirror Entity and kill opponents from nowhere. This is going to be useful against things like Chishiro, I think.

There are lots of tricky ways to generate value, counter spells, and make your opponent's life hard, all while adding to your board. These effects really start to explode with something like Reflections of Littjara in play, too.

Aside from interaction on a body we also have the usual stuff like Counterspell, Path to Exile, Swords to Plowshares, and Cyclonic Rift.

Getting Through For Damage

The deck will want to win through combat damage. And Merfolk specializes in getting in for damage. Aside from several ways to tap opposing blockers, we have island walk. So, anyone with an island (Haldan/Pako, Orvar, Arcades, Tatsunari, Ezuri, etc.) and the non-blue decks in your group, we can give an island with things like Aquitect's Will.

Card Advantage And Ramp

Aside from the usual Sol Ring, Farseek the deck can really pump out extra mana with things like Hakbal of the Surging Soul, Nicanzil, Current Conductor, and Cryptolith Rite which works great with Merrow Commerce! All this extra mana will be put to good use casting all the cards you'll draw.

Speaking of drawing cards, as you requested, the deck is very draw-focused. Aside from Thrasios, Triton Hero, we have several other draw engines, with the ones pictured above being some of the best. However, we also have:

• Vanquisher's Banner
• Kindred Discovery
• Tishana, Voice of Thunder
• Tatyova, Benthic Druid
• Seafloor Oracle

Note On Tutors

I wanted to mention these cards:

• Forerunner of the Heralds
• Merrow Harbinger
• Seahunter

Because they are technically tutors as they allow you to search for a Merfolk. However, I don't think they fall into the category of things your playgroup mentioned and certainly aren't CEDH-level stuff like Demonic Tutor and stuff. That said, if they aren't allowed, let me know.