# Poseidon: the voyage and the grudge

Phase-one baseline, 2026-09-25 UTC. Commander: **Poseidon, Earth-Shaker**, exactly as printed in [the shared proposal](../../clash.md): {4}{G}{U}, legendary enchantment creature — God, 6/6, additional land play and the three landfall modes. No ward. The commander is outside the [99-card baseline](baseline.txt). All baseline entries are existing cards; no custom support cards have been designed at this stage.

## Story and the decisions it creates

Poseidon's character combines the sea's generosity with a grudge that can make the world itself resist a traveler. This is an adversary's view of the Odyssey, with the Earth-Shaker's battle against Polybotes as the explanation for a landscape that keeps changing. Existing creatures are functional stand-ins for maritime danger, not claims that Magic's named characters belong to Greek myth.

1. **Safe passage is a favor.** Homeric Hymn 22 calls on Poseidon to help voyagers and also identifies him with earthquakes and horses. Early land development is a route through his domain; the choice to spend a fetch now for speed or hold it for another player's turn expresses control over passage. [Homeric Hymn 22, translated in Theoi's classical-source collection](https://www.theoi.com/Olympios/Poseidon.html).
2. **The insult becomes a grudge.** After Odysseus blinds Polyphemus, the Cyclops appeals to Poseidon to obstruct his homecoming. The deck should remember a dangerous opposing attacker or engine through focused interaction, rather than indiscriminately resetting everyone. This is a mechanical adaptation of the petition and its consequences. [Homer, Odyssey 9, especially 528–535](https://www.theoi.com/Text/HomerOdyssey9.html).
3. **An apparent arrival becomes a wreck.** In Odyssey 5, Poseidon's wave breaks the raft near the end of Odysseus's voyage. The commander or Aetherize can turn a confident advance into another journey. A saved landfall trigger costs earlier acceleration; deciding when to release it supplies the dramatic choice. [Homer, Odyssey 5, especially 365–387](https://www.theoi.com/Text/HomerOdyssey5.html).
4. **The map is a weapon.** Poseidon tears away part of Kos and throws it at Polybotes; the fragment becomes Nisyros. Ramp, land recovery, and landfall make the landscape an active participant in battle. The custom package should translate an island-sized act of violence into a spectacular answer without destroying opponents' mana bases. [Apollodorus and Strabo on Polybotes](https://www.theoi.com/Gigante/GigantePolybotes.html).
5. **The traveler can survive the god.** Leucothea's veil, Athena's help, and the river's refuge let Odysseus survive the storm. Protection, resilient threats, and counterplay matter to this story: a god's wrath is immense, but its victim can still make choices. The deck must turn a temporary opening into an attack, not keep every traveler at sea forever. [Homer, Odyssey 5, 333–463](https://www.theoi.com/Text/HomerOdyssey5.html).

These beats need not appear in chronological order. A land can be a resource, a monster's approach, or the instrument of a reversal; the pilot chooses the chapter through Poseidon's mode selection. Phase two should make that narrative explicit with ten connected designs, including at least one extraordinary answer and one extraordinary resource engine.

## Playing the baseline

**Early development.** Keep approximately three lands and an early ramp or draw play. Prioritize green access for the two-mana land spells; establish blue before passing with Counterspell. Forty lands support the extra-land permissions without making the god mandatory. Sol Ring is the only premium burst of early mana. Seven conventional ramp cards cost two mana; Exploration is fast only when supplied with extra lands. Oracle and Aesi are later accelerators with bodies opponents can remove.

**Commander turn.** Normally aim to cast Poseidon on turns four through six while retaining an unused land play. If six lands already pay his cost, play a seventh after he resolves, take two cards or a Kraken, then use his additional play for the other mode. A fetch land supplies another entrance when sacrificed, but only one mode of each kind is available each turn. If every mode has been used, further entrances provide no fourth reward. Holding an uncracked fetch for the next player's turn earns a fresh menu, but forfeits the mana it could have supplied now. Walking Atlas can put a land in during an opponent's turn after summoning sickness ends; it has no untap engine.

**Operate without the god.** Aesi, Tatyova, Tracker, Rhystic Study, and the other draw cards keep the hand stocked. Rampaging Baloths, Avenger, Titania, Koma, and the sea monsters establish threats on their own. This is a real 99 before replacements, with 22 creature cards and several independent token engines. It does not need Poseidon to make an opposing removal spell relevant.

**Recovery.** Land ramp survives most creature sweepers. Recast the god when a land in hand gives immediate value; otherwise deploy a different threat and a draw engine. Life from the Loam replenishes fetches, Splendid Reclamation rebuilds sacrificed lands, and Regrowth is one finite recovery spell. Do not commit every monster just because the mana is available. Heroic Intervention handles destruction, not exile or bounce. Whelming Wave returns Poseidon himself, so use it knowing the god will need recasting; it preserves Kraken/Leviathan/Octopus/Serpent bodies.

**Closing the game.** Attack with a developed board. Serpent of Yawning Depths supplies sea-monster evasion, Garruk's Uprising and Surrak supply trample, Koma turns a successful hit into more attackers, and Spawning Kraken rewards a sea-monster hit. A pair of 6/6 Krakens plus a larger threat presents meaningful damage every turn; the army grows if allowed another lap. Cyclonic Rift or a selective bounce opens one attack, after which opponents can rebuild. This is visible battlefield pressure rather than an immediate table-kill package from hand. Surrak grants haste only to subsequent nontoken creatures, not to Poseidon's newly created Krakens. Poseidon's own 6/6 body can threaten commander-damage kills through repeated successful attacks; he does not have intrinsic trample.

## Counts, mana, and overlap

[roles.json](roles.json) assigns every card exactly one primary role. [verified-cards.json](verified-cards.json) records retrieved Oracle text, identity, types, mana values, and legality.

| Primary role | Count | Interpretation |
| --- | ---: | --- |
| Lands | 40 | 20 basics, 20 nonbasics; six ordinary fetches plus Myriad Landscape |
| Ramp | 12 | Sol Ring, Signet, seven land-development spells/Exploration, Elder, Oracle, Atlas |
| Draw and selection | 12 | Includes land-based resource bodies and combat-independent draw |
| Targeted interaction | 12 | Six permanent answers, four counters, two graveyard answers |
| Sweepers / broad reversals | 3 | Aetherize, Cyclonic Rift, Whelming Wave |
| Protection and recovery | 5 | Two protection spells, three finite recovery cards |
| Threats and offensive engines | 15 | Sea monsters, landfall armies, and combat enablers |
| **Total** | **99** | Commander is additional |

The nonland mana-value distribution is **1: eight; 2: nineteen; 3: seven; 4: seven; 5: four; 6: six; 7: six; 9: one; 10: one**. Mean nonland mana value is **3.59**. Deep-Sea Kraken is ordinarily suspended for three, making its printed mana value ten misleading for early sequencing. There are 27 one- or two-mana spells, with enough cheap answers to avoid every turn being tap-out ramp.

The twenty basics are eleven Forests and nine Islands. Most duals can enter untapped; fetch targets include Tropical Island and Breeding Pool where their printed land types permit. Flooded Strand is legal in a UG deck and searches for these Island duals or basic Islands; it cannot find a basic Forest. Evolving Wilds and Terramorphic Expanse are slower mana but deliberate triggers that can be saved. Myriad Landscape is a slow ramp land. Only Reliquary Tower and Scavenger Grounds are utility lands with no eventual colored-mana function.

Important overlap, already counted once: Aesi accelerates while classified as draw; Growth Spiral puts in a land while classified as draw; Oracle and Courser turn the library's top card into land access in different ways. Tracker is a growing attacker and a mana-consuming draw engine. Titania and Scourge of Fleets supply recovery and interaction while classified as threats. Kiora Bests the Sea God supplies a large creature, a temporary opening, and theft. Otawara is an additional bounce answer within lands. Scavenger Grounds is a third graveyard answer beyond Lantern and Ooze. Regrowth can recover a spell once, but there is no Archaeomancer-style repeatable recursion package.

Force of Vigor is the **one** spell with a free alternative cost. Other counters and protection require mana. Beast Within and Force of Vigor can destroy any god's enchantment body; Pongify, Rapid Hybridization, Reality Shift, and Resculpt also answer their creature bodies. Exile interaction must stay in the final deck even though landfall bounce is the most thematic answer. The list has no premium fast-mana pile or land-untap engine.

## Ten strong replacement candidates for phase two

These are functional benchmarks, not designs or a frozen mapping yet. Preserve the baseline as evidence and replace exactly ten after the orchestrator's comparison.

| Existing card | Proposed custom role | What the replacement must preserve or improve |
| --- | --- | --- |
| Cyclonic Rift | Signature answer | An outrageous reversal that opens attacks; avoid a repeatable all-opponent reset |
| Force of Vigor | Answer | Efficient permanent interaction against the enchantment gods and other engines |
| Aetherize | Answer | A frightening response to a committed attack with meaningful defensive choice |
| Reality Shift | Answer | Permanent creature removal, including exile/graveyard denial |
| Rhystic Study | Signature resource engine | A dramatic, independent source of cards with exploitable limits |
| Mystic Remora | Resource | Early access to cards, avoiding endless tax decisions |
| Rishkar's Expertise | Resource | A big finite refill that pays off established power |
| Exploration | Resource | Land access or scheduling that expresses command over passage |
| Kiora Bests the Sea God | Threat / climax | A sea-monster payoff that makes an eventual attack plausible |
| Koma, World-Eater | Threat / closer | An astonishing but earned attack that leaves an army |

The package should replace recognizable power, not ten weak filler cards. The signature cards should surprise an experienced high-power Commander player in ordinary plausible board states. Four answers and four resources can carry most of the spectacle, while the last two slots ensure the deck still tries to win. No lands or graveyard-interaction slots need to be cut to achieve this mapping.

## Preliminary constraint check and remaining questions

No extra-turn or extra-combat cards, mass land destruction, tutors for a deterministic win, land-untap engines, sacrifice-loop package, token doublers, or alternative-win cards are included. The selected Koma is **World-Eater**, not Cosmos Serpent: it rewards combat instead of repeatedly tapping opponents' permanents. Stormtide Leviathan is deliberately absent because its combat restriction would excessively constrain Athena. Hullbreaker Horror and repeated spell-recursion creatures are absent because this deck needs temporary openings rather than a bounce lock. Boseiju is absent because Life from the Loam could turn it into recurring land removal. Trench Behemoth untaps only itself and returns one's own lands; Atlas cannot untap itself, so this pairing does not create unlimited land entries.

These are design checks, not actual playtesting or proof that all future cross-deck interactions are safe. The chief review concerns are the rate of off-turn Kraken production, whether evasion ends games before repeated tempo becomes frustrating, and whether fifteen offensive slots leave too many expensive opening hands. Custom design and cold review must check all forty new cards and stolen/copy interactions before an art freeze.

All 81 distinct existing names in the baseline were retrieved through the [Scryfall collection API](https://scryfall.com/docs/api/cards/collection), with singleton/color-identity/Commander-legality checks recorded locally. The [official Commander banned list](https://magic.wizards.com/en/banned-restricted-list) was checked independently on 2026-09-25 UTC; none of these entries appears in its Commander section. The only intended format exception remains the custom god.

## Phase-two final list and illustrative checks

The [final 99](final.txt) and [ten replacement specifications](custom-cards.yaml) implement the narrative above. [replacements.md](replacements.md) supersedes the earlier candidate table with the exact mapping and final curve. The commander, baseline, and forty-land foundation are unchanged. The final list replaces Koma, Kiora's Saga, Rhystic Study, Mystic Remora, Cyclonic Rift, and the other five listed slots rather than adding custom power on top of them. Its core wins remain sea-monster attacks, landfall bodies, trample, and evasion. The following are hand-worked design checks, **not recorded playtests**.

**Representative opening.** A seven-card hand of Forest, Island, Misty Rainforest, Nature's Lore, Poseidon's Hippocamps, Polyphemus's Prayer, and Rampaging Baloths has lands, two development options, an answer, and a payoff. Turn one Forest; turn two Island and Nature's Lore finding Breeding Pool. If the pilot pays two life for Pool, that life loss could enable Prayer, but the hand still needs the remaining mana to cast it. On turn three Hippocamps grants another land play; a land drawn for the turn and the held fetch can develop toward a turn-four god. If no further lands arrive, the opening still has four lands after the fetch and two live two-mana plays; it does not assume a guaranteed six-mana turn. Cast Hippocamps after ramp if colored mana or additional land supply is uncertain.

**Commander turn.** With six lands and a Forest plus Misty Rainforest in hand, cast Poseidon before using the normal land play. Play Forest and choose the Kraken mode. The extra permission lets the pilot play Misty and choose draw-two. Either crack it for the bounce mode now, or save its activation for another player's turn. With Hippocamps present, cracking it during that player's combat can draw two from Hippocamps and use a fresh Poseidon mode. Keeping the fetch costs the mana the fetched land could otherwise supply. Removing either creature before the land enters prevents that creature's trigger; it does not erase a trigger already on the stack.

**Creature wipe and rebuild.** Suppose Zeus casts Blasphemous Act and its 13 damage kills the unprotected Poseidon, Hippocamps, and a Kraken. Eight lands, Leucothea's Veil, and a small hand survive. Casting The Sea Makes Way for six can stock the hand and put up to four new lands in tapped; the pilot may have to discard at cleanup and remains open to attack. On the next turn, land mana can support either recasting Poseidon for eight or casting Triton plus a second threat. Choosing the latter is a legitimate recovery line with the god still in the command zone. A draw that lacks the signature can instead cast Tatyova or Aesi and make ordinary land drops, while the preserved lands fund cheap interaction. The deck does not require the six-mana signature to function.

**Signature reversal.** With seven lands and an untapped 6/6 Poseidon, Nisyros Falls can find two basics, raise him to 15/15, and damage every opposing creature for 15. Targeted removal before resolution stops the whole spell, so leaving protection mana matters. Opponents' enchantments, artifacts, lands, and hands survive. The pilot still needs a legal attack and a way past any surviving indestructible blocker. If only Poseidon attacks, one hit is not a 21-point commander-damage kill by itself. This is a decisive swing that opens a game, not an automatic table elimination.

**Late attack.** Assume Triton and two old 6/6 Kraken tokens can attack, with eight lands available. Attack with all three and use Triton's trigger to tap three lands for three temporary attacking 4/4 Krakens. The attack represents 28 trampling power: 4 + 12 + 12. The other five lands remain available for interaction. One opponent who has fallen below that total may be eliminated, but blockers, targeted removal of Triton's trample effect, or an opposing instant can change the result. The three new tokens are sacrificed at end of combat. A later Trojan Ketos attack can force a defender to return two nonland permanents, but that defender chooses which and gets another turn to redeploy cards if they survive. Pressure therefore continues toward a winner instead of making each reversal the start of another empty-board rebuilding cycle.

**Final resource audit.** The land count and primary role totals remain unchanged, with 24 creature cards and a mean nonland mana value of 3.59. Lantern, Ooze, and Scavenger Grounds still provide three separate graveyard-interaction cards. The two signatures function without the commander, and each custom permanent can be removed by ordinary interaction in the other decks. The final deck has no free alternative-cost spell after replacing Force of Vigor. Its additional power is concentrated in the ten thematic cards, while a substantial existing core still supplies mana, answers, and combat finishers.