Invasion of Segovia // Caetus, Sea Tyrant of Segovia
Battle — Siege // Legendary Creature — Serpent
(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When this Siege enters, create two 1/1 blue Kraken creature tokens with trample.
- CMC
- 3
- Mana cost
- Color identity
- U
- Rarity
- rare
- Set
- March of the Machine Promos
- Price
- —
- EDHREC rank
- #5387
Invasion of Segovia // Caetus, Sea Tyrant of Segovia enters as a battle that immediately floods the board with three 1/1 Kraken tokens, and flipping it into Caetus turns every future noncreature spell into a free attack trigger — that's a lot of pressure stapled to a three-mana enchantment-adjacent permanent. In Jeskai Ascendancy shells or under Kasla, the Broken Halo, where spells fire rapidly and tokens are currency, this card earns its slot.
Best Commanders
Commanders with the highest synergy
Kasla, the Broken Halo
Kasla, the Broken Halo runs Invasion of Segovia // Caetus, Sea Tyrant of Segovia in nearly 70% of builds because Kasla's spell-recycling engine means you're casting noncreature spells constantly, which Caetus rewards with repeated attack triggers on your growing Kraken army.
The Watcher in the Water
The Watcher in the Water wants as many Krakens and tentacle-adjacent tokens as it can get, and Invasion of Segovia // Caetus, Sea Tyrant of Segovia delivers three bodies on entry while Caetus keeps producing pressure every time the deck casts an instant or sorcery.
Ovika, Enigma Goliath
Ovika, Enigma Goliath already rewards every noncreature spell with tokens, so Invasion of Segovia // Caetus, Sea Tyrant of Segovia layers on an additional payoff — cast a big spell, get Ovika's Goblin tokens and trigger Caetus's attack clause at the same time.
Octavia, Living Thesis
Octavia, Living Thesis is built around casting as many instants and sorceries as possible to build toward an 8/8 threat, and Invasion of Segovia // Caetus, Sea Tyrant of Segovia converts that same spell density into combat pressure, giving the deck a second axis of attack.
Magnus the Red
Magnus the Red generates tokens off every noncreature spell, and Invasion of Segovia // Caetus, Sea Tyrant of Segovia fits naturally into that pattern — flip Caetus and each Magnus-fueled spell now also swings your Krakens in, stacking damage from multiple angles simultaneously.
Format Analysis
Where it lives, where it can’t
| Format | Verdict |
|---|---|
| commander | legal |
| legacy | legal |
| modern | legal |
| pioneer | legal |
| standard | not legal |
| vintage | legal |
| pauper | not legal |
| oathbreaker | legal |
Commander is where Invasion of Segovia // Caetus, Sea Tyrant of Segovia does its best work: 100-card spell-dense decks give Caetus plenty of triggers, and the three Kraken tokens on entry matter more in a format where card advantage accumulates slowly. In Modern and Pioneer, the three-mana cost and battle-type setup are too slow and convoluted for a format that punishes do-nothing permanents, so it sees essentially no competitive play there. Legacy and Vintage have the raw power density to flip it quickly, but those formats have no patience for a card whose ceiling requires multiple untap steps to realize. Oathbreaker is the other format worth watching — the compressed game length and commander-spell synergy can let Caetus close games faster than in full Commander.
Key Combos
Combo lines featuring this card
Jeskai AscendancyInvasion of Segovia // Caetus, Sea Tyrant of Segovia
Infinite storm count; Infinite self-discard triggers; Infinite untap of creatures you control; Infinite draw triggers; Infinite looting; Infinite mana creatures you control can produce; Infinite magecraft triggers; Infinitely large creatures you control until end of turn
View on Commander Spellbook ↗
StormsplitterInvasion of Segovia // Caetus, Sea Tyrant of SegoviaHaze of Rage
Infinite LTB; Infinite ETB; Infinite storm count; Infinite creature tokens with haste; Infinite magecraft triggers; Infinitely powerful creatures you control until end of turn
View on Commander Spellbook ↗
StormsplitterInvasion of Segovia // Caetus, Sea Tyrant of SegoviaReiterate
Infinite LTB; Infinite ETB; Infinite storm count; Infinite creature tokens with haste; Infinite magecraft triggers; Infinite copies of instant and sorcery spells on the stack
View on Commander Spellbook ↗
Invasion of Segovia // Caetus, Sea Tyrant of SegoviaIntruder AlarmRecruit the Worthy
Infinite creature tokens; Infinite ETB; Infinite magecraft triggers; Infinite mana creatures you control can produce; Infinite storm count; Infinite untap of creatures; Infinite untap of creatures you control
View on Commander Spellbook ↗
StormsplitterInvasion of Segovia // Caetus, Sea Tyrant of SegoviaSearing Touch
Infinite LTB; Infinite ETB; Infinite damage; Infinite storm count; Infinite creature tokens with haste; Infinite magecraft triggers
View on Commander Spellbook ↗Price Context
Current price
unknown tier
Price data for Invasion of Segovia // Caetus, Sea Tyrant of Segovia isn't confirmed in our current feed, so check Scryfall or your preferred vendor for the live number. Given its narrow but real demand spike in Kasla builds, it's worth grabbing a copy before a high-profile decklist pushes the price up.
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Sources
Updated . Data from Scryfall, EDHREC, and Commander Spellbook.